# Workloads Status Audit Use this document to track the technical hardening progress of the Workloads directory. All 301 wait event reference cards are listed below. Hardened files have been rigorously reviewed and expanded with deep technical descriptions. | Status | Category | Name | Summary | Link | | :--- | :--- | :--- | :--- | :--- | | ✅ Hardened | Activity | ApplyWorkerMain | This wait event occurs when the **Logical Replication Apply Worker** is idling between transaction packets. Once a lo... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/ApplyWorkerMain.md) | | ✅ Hardened | Activity | ArchiverMain | This wait event occurs when the **Archiver** process is idling between cycles. Its primary role is to monitor the `pg... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/ArchiverMain.md) | | ✅ Hardened | Activity | AutoVacuumWorkerMain | This wait event occurs when an **Autovacuum Worker** is transitioning between tasks. Once a worker is spawned, it pro... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/AutoVacuumWorkerMain.md) | | ✅ Hardened | Activity | AutovacuumMain | This wait event occurs when the **Autovacuum Launcher** is idling between its scheduled catalog scans. The launcher's... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/AutovacuumMain.md) | | ✅ Hardened | Activity | BgwriterHibernate | This wait event represents the **Dynamic Power-Saving** mode of the buffer management system. To minimize unnecessary... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/BgwriterHibernate.md) | | ✅ Hardened | Activity | BgwriterMain | This wait event occurs when the **Background Writer** is idling between its scheduled cleaning rounds. The BgWriter's... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/BgwriterMain.md) | | ✅ Hardened | Activity | CheckpointerMain | This wait event occurs when the **Checkpointer** is idling between scheduled checkpoint cycles. It is the steady-stat... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/CheckpointerMain.md) | | ✅ Hardened | Activity | CheckpointerShutdown | This wait event indicates the **Final Durability Barrier**. To ensure that the database can restart instantly without... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/CheckpointerShutdown.md) | | ✅ Hardened | Activity | IoWorkerMain | This wait event indicates an **Available Asynchronous Slot**. Introduced to support modern high-throughput storage in... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/IoWorkerMain.md) | | ✅ Hardened | Activity | LogicalApplyMain | This wait event indicates a **Logical Data Underflow**. The Apply Worker is the primary engine on the subscriber side... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Logical/LogicalApplyMain.md) | | ✅ Hardened | Activity | LogicalLauncherMain | This wait event occurs when the **Logical Replication Launcher** process is in its steady-state idle loop. It is the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Logical/LogicalLauncherMain.md) | | ✅ Hardened | Activity | LogicalParallelApplyMain | This wait event indicates an **Available Parallel Replication Slot**. To handle massive transaction volumes that a si... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Logical/LogicalParallelApplyMain.md) | | ✅ Hardened | Activity | ParallelWorkerMain | This wait event occurs when a **Parallel Worker** is idling in its main loop. This state typically occurs during the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Parallel/ParallelWorkerMain.md) | | ✅ Hardened | Activity | RecoveryWalAll | This wait event indicates that the **Recovery Engine** is caught up and is waiting for more transaction data to proce... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/RecoveryWalAll.md) | | ✅ Hardened | Activity | RecoveryWalStream | This wait event indicates that the **Standby Replay Process** is caught up with the primary's WAL stream. It represen... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/RecoveryWalStream.md) | | ✅ Hardened | Activity | ReplicationSlotsyncMain | This wait event occurs when the **Replication Slot Sync** process is idling between its scheduled synchronization cyc... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/ReplicationSlotsyncMain.md) | | ✅ Hardened | Activity | ReplicationSlotsyncShutdown | This wait event indicates an **Administrative Idle State**. Introduced to support failover-capable logical replicatio... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/ReplicationSlotsyncShutdown.md) | | ✅ Hardened | Activity | SysloggerMain | This wait event occurs when the **System Logger** is idling. The process is designed to be asynchronous; backends wri... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Maintenance/SysloggerMain.md) | | ✅ Hardened | Activity | WalReceiverMain | This wait event occurs when the **WAL Receiver** on a standby server is idling. It means the receiver has established... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalReceiverMain.md) | | ✅ Hardened | Activity | WalSenderMain | This wait event occurs when a **WAL Sender** process is idling in its main loop. It indicates that the sender has fin... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalSenderMain.md) | | ✅ Hardened | Activity | WalSenderWaitWal | This wait event indicates a **Primary-Side Durability Lag**. To ensure data integrity, a WAL Sender cannot stream rec... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalSenderWaitWal.md) | | ✅ Hardened | Activity | WalSummarizerWal | This wait event indicates that the **Incremental Backup Pipeline is Caught Up**. The WAL Summarizer is a background p... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalSummarizerWal.md) | | ✅ Hardened | Activity | WalWriterHibernate | This wait event represents the **Dynamic Power-Saving** mode of the durability system. To minimize unnecessary system... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalWriterHibernate.md) | | ✅ Hardened | Activity | WalWriterMain | This wait event occurs when the **WAL Writer** is idling between its scheduled flushing rounds. The process operates ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Activity/Replication/WalWriterMain.md) | | ✅ Hardened | BufferPin | BufferPin | This wait event indicates a synchronization stall at the **Buffer Management Layer**. Unlike locks, which protect the... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/BufferPin/BufferPin.md) | | ✅ Hardened | CPU | CPU | This state indicates **Computational Saturation**. While other wait events represent time spent idling, the "CPU wait... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/CPU/CPU.md) | | ✅ Hardened | CPU | ExpressionEvaluation | This state indicates **Query Logic Complexity**. Every time you add a non-trivial operation to a query—like a `CASE` ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/CPU/ExpressionEvaluation.md) | | ✅ Hardened | CPU | MemoryAlgorithms | This state indicates **In-Memory Organizational Overhead**. Even when data does not spill to disk, the CPU must still... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/CPU/MemoryAlgorithms.md) | | ✅ Hardened | CPU | Spinning | This state indicates **Micro-Contention Heat**. Before a process officially "waits" (which involves an expensive cont... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/CPU/Spinning.md) | | ✅ Hardened | CPU | TupleProcessing | This state indicates **Data Throughput Saturation**. Once the pages are in memory and the locks are acquired, the CPU... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/CPU/TupleProcessing.md) | | ✅ Hardened | Client | ClientRead | This wait event is the database's version of a "Bored Waiter." It indicates that the backend has finished its previou... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/ClientRead.md) | | ✅ Hardened | Client | ClientWrite | This wait event indicates a **Network Throughput Bottleneck**. The database has successfully executed the query and i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/ClientWrite.md) | | ✅ Hardened | Client | GssOpenServer | This wait event indicates an **External Authentication Delay**. When a cluster is configured with GSSAPI security, th... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/GssOpenServer.md) | | ✅ Hardened | Client | LibpqwalreceiverConnect | This wait event indicates a **Replication Pipeline Initialization Barrier**. Before a standby can begin replaying dat... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/LibpqwalreceiverConnect.md) | | ✅ Hardened | Client | LibpqwalreceiverReceive | This wait event indicates a **Replication Stream Idle state**. Once a connection is established, the standby process ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/LibpqwalreceiverReceive.md) | | ✅ Hardened | Client | SslOpenServer | This wait event indicates an **Encryption Negotiation Delay**. To establish a secure channel, the database and the cl... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/SslOpenServer.md) | | ✅ Hardened | Client | WaitForStandbyConfirmation | This wait event indicates a **Physical Durability Consensus Barrier**. While `IPC:SyncRep` is the generic wait event ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/WaitForStandbyConfirmation.md) | | ✅ Hardened | Client | WalSenderWaitForWal | This wait event indicates a **Primary-Side Durability Lag**. To ensure data integrity, a WAL Sender cannot stream rec... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/WalSenderWaitForWal.md) | | ✅ Hardened | Client | WalSenderWriteData | This wait event indicates a **Network Congestion Bottleneck**. The database has already successfully read the WAL dat... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Client/WalSenderWriteData.md) | | ✅ Hardened | Extension | Extension | This wait event serves as a **Generic Container** for synchronization logic implemented within third-party extensions... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Extension/Extension.md) | | ✅ Hardened | IO | AioIoCompletion | This wait event indicates a **Storage Performance Barrier**. Unlike traditional synchronous I/O (where the backend bl... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/AIO/AioIoCompletion.md) | | ✅ Hardened | IO | AioIoUringExecution | This wait event indicates a **Kernel-Space I/O Bottleneck**. In the `io_uring` architecture, the database hands over ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/AIO/AioIoUringExecution.md) | | ✅ Hardened | IO | AioIoUringSubmit | This wait event indicates an **In-Memory Coordination Logjam**. To minimize the cost of system calls, `io_uring` uses... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/AIO/AioIoUringSubmit.md) | | ✅ Hardened | IO | BasebackupRead | This wait event indicates the **Bulk Read Throughput** of a backup operation. During a base backup, the engine must p... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BaseBackup/BasebackupRead.md) | | ✅ Hardened | IO | BasebackupSync | This wait event indicates a **Data Durability Milestone**. During a physical backup, Postgres must ensure that the co... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BaseBackup/BasebackupSync.md) | | ✅ Hardened | IO | BasebackupWrite | This wait event indicates a **Bulk Write Throughput Bottleneck**. During a base backup, the engine must physically co... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BaseBackup/BasebackupWrite.md) | | ✅ Hardened | IO | BuffileRead | This wait event indicates an **On-Disk Query Execution Stall**. While ordinary data reads are cached in shared buffer... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BufFile/BuffileRead.md) | | ✅ Hardened | IO | BuffileTruncate | This wait event indicates a **Temporary Resource Cleanup Penalty**. To prevent temporary storage (governed by `work_m... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BufFile/BuffileTruncate.md) | | ✅ Hardened | IO | BuffileWrite | This wait event indicates an **On-Disk Query Execution Overhead**. When the dataset for a sort or a join cannot fit e... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/BufFile/BuffileWrite.md) | | ✅ Hardened | IO | ControlFileRead | This wait event indicates a **Core Meta-Data Retrieval stall**. The Control File is the most critical file in a Postg... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ControlFile/ControlFileRead.md) | | ✅ Hardened | IO | ControlFileSync | This wait event represents a critical **Integrity Barrier** in the Postgres architecture. The `pg_control` file conta... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ControlFile/ControlFileSync.md) | | ✅ Hardened | IO | ControlFileSyncUpdate | This wait event indicates a **State Transition Durability Barrier**. Every time the database changes its fundamental ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ControlFile/ControlFileSyncUpdate.md) | | ✅ Hardened | IO | ControlFileWrite | This wait event indicates a **Core Meta-Data Update Barrier**. While `ControlFileSyncUpdate` represents the final dur... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ControlFile/ControlFileWrite.md) | | ✅ Hardened | IO | ControlFileWriteUpdate | This wait event indicates an **Active State Change Bottleneck**. It is specifically triggered during the "Update" pha... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ControlFile/ControlFileWriteUpdate.md) | | ✅ Hardened | IO | CopyFileCopy | This wait event indicates a **Physical Cloning Barrier**. While `CopyFileRead` and `CopyFileWrite` track the individu... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/CopyFile/CopyFileCopy.md) | | ✅ Hardened | IO | CopyFileRead | This wait event indicates a **Cloning Throughput Bottleneck**. When you create a new database, Postgres does not gene... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/CopyFile/CopyFileRead.md) | | ✅ Hardened | IO | CopyFileWrite | This wait event indicates a **Cloning Write Throughput Bottleneck**. While `CopyFileRead` tracks the source, `CopyFil... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/CopyFile/CopyFileWrite.md) | | ✅ Hardened | IO | DSMFillZero | This wait event represents a **Memory Allocation Barrier**. When a parallel query starts, the leader backend must cre... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DSM/DSMFillZero.md) | | ✅ Hardened | IO | DataFileExtend | This wait event indicates a **Physical File Expansion Stall**. When a table or index runs out of free space in its ex... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileExtend.md) | | ✅ Hardened | IO | DataFileFlush | This wait event indicates a **Physical Data Durability Barrier**. While standard writes to the OS page cache are fast... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileFlush.md) | | ✅ Hardened | IO | DataFileImmediateSync | This wait event indicates an **Urgent Durability Requirement**. Unlike background flushing (which is paced by the che... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileImmediateSync.md) | | ✅ Hardened | IO | DataFilePrefetch | This wait event indicates an **I/O Prediction Stutter**. Prefetching is an optimization where Postgres "looks ahead" ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFilePrefetch.md) | | ✅ Hardened | IO | DataFileRead | This wait event represents a synchronous stall while the backend process waits for the operating system to deliver a ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileRead.md) | | ✅ Hardened | IO | DataFileSync | This wait event represents the **Durability Barrier** for actual table and index data. While Write-Ahead Logs are syn... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileSync.md) | | ✅ Hardened | IO | DataFileTruncate | This wait event indicates a **Physical Space Reclamation Barrier**. Unlike a simple `DELETE` (which leaves the file s... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileTruncate.md) | | ✅ Hardened | IO | DataFileWrite | This wait event represents a synchronous **Storage Writing Stall**. While Postgres attempts to perform most writes in... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DataFile/DataFileWrite.md) | | ✅ Hardened | IO | DsmAllocate | This wait event indicates a **Parallel Resource Startup Penalty**. To execute a query in parallel, Postgres must crea... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DSM/DsmAllocate.md) | | ✅ Hardened | IO | DsmFillZeroWrite | This wait event indicates a **Memory Initialization Penalty**. When a DSM segment is backed by a file (common on many... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/DSM/DsmFillZeroWrite.md) | | ✅ Hardened | IO | LockFileAddtodatadirRead | This wait event indicates a **Runtime Identity Verification stall**. The `postmaster.pid` file is the ultimate author... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileAddtodatadirRead.md) | | ✅ Hardened | IO | LockFileAddtodatadirSync | This wait event indicates a **Runtime Authority Durability Barrier**. To prevent a second Postgres instance from acci... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileAddtodatadirSync.md) | | ✅ Hardened | IO | LockFileAddtodatadirWrite | This wait event indicates a **Runtime Identity Update Barrier**. It represents the initial act of handing new process... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileAddtodatadirWrite.md) | | ✅ Hardened | IO | LockFileCreateRead | This wait event indicates a **Startup Identity Conflict Check**. Before a new Postgres instance can claim a data dire... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileCreateRead.md) | | ✅ Hardened | IO | LockFileCreateSync | This wait event indicates a **Runtime Authority Durability Barrier**. To prevent a race condition where a second Post... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileCreateSync.md) | | ✅ Hardened | IO | LockFileCreateWrite | This wait event indicates an **In-Flight Authority Write Barrier**. It represents the act of handing the server's ide... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileCreateWrite.md) | | ✅ Hardened | IO | LockFileRecheckdatadirRead | This wait event indicates a **Runtime Identity Verification stall**. To prevent data corruption, Postgres processes p... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LockFile/LockFileRecheckdatadirRead.md) | | ✅ Hardened | IO | LogicalRewriteCheckpointSync | This wait event indicates a **Replication State Durability Barrier**. When a table is rewritten (e.g., during `VACUUM... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteCheckpointSync.md) | | ✅ Hardened | IO | LogicalRewriteMappingSync | This wait event indicates a **Transaction-Level Durability Barrier**. Before a transaction that rewrote a table can b... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteMappingSync.md) | | ✅ Hardened | IO | LogicalRewriteMappingWrite | This wait event indicates an **Active Mapping Stream Bottleneck**. It represents the initial act of handing the mappi... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteMappingWrite.md) | | ✅ Hardened | IO | LogicalRewriteSync | This wait event indicates a **Maintenance Completion Durability Barrier**. It represents the "Point of No Return" for... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteSync.md) | | ✅ Hardened | IO | LogicalRewriteTruncate | This wait event indicates a **Metadata Cleanup Barrier**. To prevent the `pg_logical/mappings/` directory from growin... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteTruncate.md) | | ✅ Hardened | IO | LogicalRewriteWrite | This wait event indicates an **In-Flight Metadata Write Barrier**. It represents the background activity of the logic... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/LogicalRewrite/LogicalRewriteWrite.md) | | ✅ Hardened | IO | RelationMapRead | This wait event is a specialized I/O operation that occurs primarily during **Database Startup** or when a backend is... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/RelationMap/RelationMapRead.md) | | ✅ Hardened | IO | RelationMapReplace | This wait event indicates a **Core Mapping Durability Barrier**. The Relation Map is a critical small file that provi... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/RelationMap/RelationMapReplace.md) | | ✅ Hardened | IO | RelationMapWrite | This wait event indicates an **In-Flight Mapping Update Barrier**. It represents the initial act of handing the updat... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/RelationMap/RelationMapWrite.md) | | ✅ Hardened | IO | ReorderBufferRead | This wait event indicates a **Logical Decoding Memory Overflow Penalty**. To keep the memory footprint of replication... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ReorderBuffer/ReorderBufferRead.md) | | ✅ Hardened | IO | ReorderBufferWrite | This wait event indicates an **Active Memory Pressure stall** in the replication pipeline. It represents the point wh... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ReorderBuffer/ReorderBufferWrite.md) | | ✅ Hardened | IO | ReorderLogicalMappingRead | This wait event indicates a **Replication Reconciliation Delay**. To correctly reconstruct a transaction that has bee... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/ReorderBuffer/ReorderLogicalMappingRead.md) | | ✅ Hardened | IO | ReplicationSlotRead | This wait event indicates a **Replication Identity Retrieval stall**. Each replication slot (whether physical or logi... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/ReplicationSlotRead.md) | | ✅ Hardened | IO | ReplicationSlotRestoreSync | This wait event indicates a **Replication State Initialization Barrier**. To ensure that a standby server or a recent... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/ReplicationSlotRestoreSync.md) | | ✅ Hardened | IO | ReplicationSlotSync | This wait event indicates a **Replication Progress Durability Barrier**. As a replica consumes data, the primary must... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/ReplicationSlotSync.md) | | ✅ Hardened | IO | ReplicationSlotWrite | This wait event indicates an **Active Slot State Update Barrier**. It represents the initial act of handing the updat... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/ReplicationSlotWrite.md) | | ✅ Hardened | IO | SlruFlushSync | This wait event indicates a **Global Metadata Durability Barrier**. SLRU is the specialized storage engine Postgres u... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/SLRU/SlruFlushSync.md) | | ✅ Hardened | IO | SlruRead | This wait event indicates that the database is waiting for **Transaction Metadata** to be read from disk. SLRUs are s... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/SLRU/SlruRead.md) | | ✅ Hardened | IO | SlruSync | This wait event indicates a **Transaction-Level Metadata Durability Barrier**. Before a transaction can be considered... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/SLRU/SlruSync.md) | | ✅ Hardened | IO | SlruWrite | This wait event indicates an **Active Metadata Write Barrier**. It represents the initial act of handing the serializ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/SLRU/SlruWrite.md) | | ✅ Hardened | IO | SnapbuildRead | This wait event indicates a **Decoding Context Retrieval stall**. To correctly interpret WAL records into logical cha... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/SnapbuildRead.md) | | ✅ Hardened | IO | SnapbuildSync | This wait event indicates a **Replication Catalog Durability Barrier**. To ensure that logical decoding can resume co... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/SnapbuildSync.md) | | ✅ Hardened | IO | SnapbuildWrite | This wait event indicates an **In-Flight Snapshot Creation Barrier**. It represents the initial act of handing the se... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/SnapbuildWrite.md) | | ✅ Hardened | IO | TimelineHistoryFileSync | This wait event indicates a **Replication Failover Durability Barrier**. Timeline history files are essential for tra... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/TimelineHistoryFileSync.md) | | ✅ Hardened | IO | TimelineHistoryFileWrite | This wait event indicates an **In-Flight Timeline Update Barrier**. It represents the initial act of handing the rece... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/TimelineHistoryFileWrite.md) | | ✅ Hardened | IO | TimelineHistoryRead | This wait event indicates a **Recovery Lineage Retrieval stall**. Timeline history files provide the engine with the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/TimelineHistoryRead.md) | | ✅ Hardened | IO | TimelineHistorySync | This wait event indicates a **Primary Promotion Durability Barrier**. When a standby takes over as the new primary, i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/TimelineHistorySync.md) | | ✅ Hardened | IO | TimelineHistoryWrite | This wait event indicates an **Active Promotion State Barrier**. It represents the initial act of handing the new tim... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/Replication/TimelineHistoryWrite.md) | | ✅ Hardened | IO | TwophaseFileRead | This wait event indicates a **Distributed Transaction Recovery stall**. When a transaction is "prepared" (using `PREP... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/TwophaseFile/TwophaseFileRead.md) | | ✅ Hardened | IO | TwophaseFileSync | This wait event indicates a **Prepared State Durability Barrier**. For a two-phase commit to be reliable across a clu... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/TwophaseFile/TwophaseFileSync.md) | | ✅ Hardened | IO | TwophaseFileWrite | This wait event indicates an **In-Flight Distributed State Barrier**. It represents the initial act of handing the se... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/TwophaseFile/TwophaseFileWrite.md) | | ✅ Hardened | IO | VersionFileSync | This wait event indicates a **Database Identity Durability Barrier**. The `PG_VERSION` file is a fundamental safety c... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/VersionFile/VersionFileSync.md) | | ✅ Hardened | IO | VersionFileWrite | This wait event indicates an **In-Flight Identity Update Barrier**. It represents the initial act of handing the vers... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/VersionFile/VersionFileWrite.md) | | ✅ Hardened | IO | WalBootstrapSync | This wait event indicates a **Cluster Genesis Durability Barrier**. Before a Postgres instance can officially be cons... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalBootstrapSync.md) | | ✅ Hardened | IO | WalBootstrapWrite | This wait event indicates an **Initial Log Stream Barrier**. It represents the first physical bytes being handed to t... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalBootstrapWrite.md) | | ✅ Hardened | IO | WalCopyRead | This wait event indicates a **Log Management Retrieval stall**. To minimize the overhead of file creation, Postgres "... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalCopyRead.md) | | ✅ Hardened | IO | WalCopySync | This wait event indicates a **Log Management Durability Barrier**. Before a recycled WAL segment can be safely used f... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalCopySync.md) | | ✅ Hardened | IO | WalCopyWrite | This wait event indicates an **Active Log Management Write Barrier**. It represents the background activity of the re... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalCopyWrite.md) | | ✅ Hardened | IO | WalInitSync | This wait event indicates a **Log Provisioning Durability Barrier**. To ensure that a crash during a write doesn't le... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalInitSync.md) | | ✅ Hardened | IO | WalInitWrite | This wait event represents a **Storage Allocation Stall**. To avoid the performance penalty of dynamic file expansion... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalInitWrite.md) | | ✅ Hardened | IO | WalRead | This wait event is primarily observed during **Crash Recovery**, **Physical Standby replay**, or **Logical Decoding**... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalRead.md) | | ✅ Hardened | IO | WalSummaryRead | This wait event indicates an **Incremental Backup Metadata Retrieval stall**. Introduced in Postgres 17, WAL summary ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalSummaryRead.md) | | ✅ Hardened | IO | WalSummaryWrite | This wait event indicates an **Incremental Backup Metadata Persistence stall**. The WAL Summarizer continuously scans... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalSummaryWrite.md) | | ✅ Hardened | IO | WalSync | This wait event is the definitive measure of **Storage Durability Latency**. While `WalWrite` measures the time to ha... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalSync.md) | | ✅ Hardened | IO | WalSyncMethodAssign | This wait event indicates a **Durability Strategy Verification stall**. Postgres supports multiple ways of telling th... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalSyncMethodAssign.md) | | ✅ Hardened | IO | WalWrite | This wait event indicates that a process is stalled while waiting for the operating system to complete a write reques... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalWrite.md) | | ✅ Hardened | IO | WalsenderTimelineHistoryRead | This wait event indicates a **Replication Handshake Retrieval stall**. When a standby connects, it often asks for the... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IO/WAL/WalsenderTimelineHistoryRead.md) | | ✅ Hardened | IPC | AppendReady | This wait event represents the **Parallel Dispatch Overhead** for complex query plans. In a `Parallel Append` node, t... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Parallel/AppendReady.md) | | ✅ Hardened | IPC | ArchiveCleanupCommand | This wait event indicates an **External Log Pruning Delay**. To prevent the WAL archive from consuming infinite disk ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/ArchiveCleanupCommand.md) | | ✅ Hardened | IPC | ArchiveCommand | This wait event indicates an **External Log Durability Barrier**. For a Point-In-Time Recovery (PITR) strategy to be ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/ArchiveCommand.md) | | ✅ Hardened | IPC | BackendTermination | This wait event indicates a **Process Lifecycle Synchronization Barrier**. It is most commonly seen during administra... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Process/BackendTermination.md) | | ✅ Hardened | IPC | BackupWaitWalArchive | This wait event indicates a **Backup Recoverability Barrier**. A physical backup is only useful if you have the WAL r... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/BackupWaitWalArchive.md) | | ✅ Hardened | IPC | BgworkerShutdown | This wait event indicates a **Component Lifecycle Synchronization Barrier**. Background workers (such as parallel que... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Process/BgworkerShutdown.md) | | ✅ Hardened | IPC | BgworkerStartup | This wait event indicates a **Parallel Orchestration Latency**. Before a parallel query can begin processing rows, th... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Process/BgworkerStartup.md) | | ✅ Hardened | IPC | BtreePage | This wait event is a specialized synchronization point for **Parallel Index Scans**. To ensure that multiple parallel... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Storage/BtreePage.md) | | ✅ Hardened | IPC | BufferIo | This wait event is the synchronization point between the database and the operating system's I/O stack. When a backen... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Storage/BufferIo.md) | | ✅ Hardened | IPC | CheckpointDelayComplete | This wait event indicates a **Durability Finalization Barrier**. Similar to `CheckpointDelayStart`, this event occurs... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Checkpoint/CheckpointDelayComplete.md) | | ✅ Hardened | IPC | CheckpointDelayStart | This wait event indicates a **Maintenance Coordination Barrier**. To ensure physical integrity during operations that... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Checkpoint/CheckpointDelayStart.md) | | ✅ Hardened | IPC | CheckpointDone | This wait event indicates that a backend is waiting for the **Checkpointer's Final Acknowledgment**. While the actual... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Checkpoint/CheckpointDone.md) | | ✅ Hardened | IPC | CheckpointStart | This wait event indicates a **Maintenance Queueing Barrier**. Checkpoints can be triggered automatically (by time or ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Checkpoint/CheckpointStart.md) | | ✅ Hardened | IPC | ExecuteGather | This wait event represents the orchestration cost of a **Parallel Query**. When a query plan includes a `Gather` node... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Parallel/ExecuteGather.md) | | ✅ Hardened | IPC | HashBatchAllocate | This wait event indicates a **Parallel Memory Provisioning Barrier**. When a join is too large to fit in memory, it i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBatchAllocate.md) | | ✅ Hardened | IPC | HashBatchElect | This wait event indicates a **Parallel Decision Barrier**. In the complex dance of a parallel join, certain tasks (li... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBatchElect.md) | | ✅ Hardened | IPC | HashBatchLoad | This wait event indicates a **Parallel Work-Balance Barrier**. In a parallel hash join, the data is typically partiti... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBatchLoad.md) | | ✅ Hardened | IPC | HashBuildAllocate | This wait event indicates a **Parallel Foundation Barrier**. It represents the very first step of a hash join: carvin... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBuildAllocate.md) | | ✅ Hardened | IPC | HashBuildElect | This wait event indicates a **Parallel Orchestration Barrier**. It occurs at the start of the join, where the engine ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBuildElect.md) | | ✅ Hardened | IPC | HashBuildHashInner | This wait event indicates a **Parallel Phase Barrier**. A hash join consists of two distinct phases: Build (where you... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBuildHashInner.md) | | ✅ Hardened | IPC | HashBuildHashOuter | This wait event indicates a **Large-Scale Join Sync Barrier**. When a join is too big for memory, Postgres must split... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashBuildHashOuter.md) | | ✅ Hardened | IPC | HashGrowBatchesDecide | This wait event indicates a **Dynamic Query Plan Re-evaluation point**. If the actual number of rows encountered duri... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBatchesDecide.md) | | ✅ Hardened | IPC | HashGrowBatchesElect | This wait event indicates an **Emergency Orchestration Barrier**. Similar to the initial batch election, this occurs ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBatchesElect.md) | | ✅ Hardened | IPC | HashGrowBatchesFinish | This wait event indicates a **Structural Re-organization Barrier**. After the rows have been re-partitioned, the meta... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBatchesFinish.md) | | ✅ Hardened | IPC | HashGrowBatchesReallocate | This wait event indicates an **Emergency Resource Provisioning Barrier**. It occurs when the engine determines it mus... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBatchesReallocate.md) | | ✅ Hardened | IPC | HashGrowBatchesRepartition | This wait event indicates an **Active Data Redistribution Barrier**. After the number of batches has been increased, ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBatchesRepartition.md) | | ✅ Hardened | IPC | HashGrowBucketsElect | This wait event indicates an **In-Memory Performance Optimization Barrier**. If a single hash batch becomes too dense... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBucketsElect.md) | | ✅ Hardened | IPC | HashGrowBucketsReallocate | This wait event indicates an **Emergency In-Memory Provisioning Barrier**. It occurs when the engine determines that ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBucketsReallocate.md) | | ✅ Hardened | IPC | HashGrowBucketsReinsert | This wait event indicates an **In-Memory Data Migration Barrier**. After the number of buckets has been doubled, ever... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Hash/HashGrowBucketsReinsert.md) | | ✅ Hardened | IPC | LogicalApplySendData | This wait event indicates an **Inter-Worker Flow Control Bottleneck**. In parallel logical replication, the leader pr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/LogicalApplySendData.md) | | ✅ Hardened | IPC | LogicalParallelApplyStateChange | This wait event indicates a **Parallel Replication Orchestration Barrier**. Because parallel apply workers must coord... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/LogicalParallelApplyStateChange.md) | | ✅ Hardened | IPC | LogicalSyncData | This wait event indicates a **Data Transfer Bottleneck** during the bootstrapping of logical replication. Before a su... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/LogicalSyncData.md) | | ✅ Hardened | IPC | LogicalSyncStateChange | This wait event indicates an **Initial Replication Handshake Barrier**. When a new table is added to a publication, a... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/LogicalSyncStateChange.md) | | ✅ Hardened | IPC | MessageQueueInternal | This wait event indicates a **Parallel Resource Handshake stall**. To stream results back to the leader, workers must... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/MessageQueue/MessageQueueInternal.md) | | ✅ Hardened | IPC | MessageQueuePutMessage | This wait event indicates an **In-Memory Flow Control Bottleneck**. Parallel workers use shared memory queues to stre... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/MessageQueue/MessageQueuePutMessage.md) | | ✅ Hardened | IPC | MessageQueueReceive | This wait event indicates a **Producer Lag** within the query execution pool. In a parallel-aware plan, the leader pr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/MessageQueue/MessageQueueReceive.md) | | ✅ Hardened | IPC | MessageQueueSend | This wait event indicates a **Producer-Consumer Bottleneck** within a parallel query. In a parallel-aware plan, worke... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/MessageQueue/MessageQueueSend.md) | | ✅ Hardened | IPC | MultixactCreation | This wait event indicates a **Shared Lock Identity Barrier**. While LWLocks handle the memory-level synchronization f... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Transaction/MultixactCreation.md) | | ✅ Hardened | IPC | ParallelBitmapScan | This wait event is a specialized synchronization point for queries using **Parallel Bitmap Index Scans**. In this exe... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Parallel/ParallelBitmapScan.md) | | ✅ Hardened | IPC | ParallelCreateIndexScan | This wait event indicates a **Bulk Table Scan Synchronization Barrier**. Parallel index creation works in phases: fir... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Parallel/ParallelCreateIndexScan.md) | | ✅ Hardened | IPC | ParallelFinish | This wait event represents the **Cleanup Overhead** of parallel execution. After all rows have been gathered, the lea... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Parallel/ParallelFinish.md) | | ✅ Hardened | IPC | ProcSignalBarrier | This wait event represents a **Global Consensus Stall**. Certain operations in Postgres require that all backends be ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/System/ProcSignalBarrier.md) | | ✅ Hardened | IPC | ProcarrayGroupUpdate | This wait event indicates an optimization of the **Visibility Bookkeeping** system. The `ProcArray` is a shared memor... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Transaction/ProcarrayGroupUpdate.md) | | ✅ Hardened | IPC | Promote | This wait event indicates a **Cluster Role Transition Barrier**. During promotion, the database must finalize all rec... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/Promote.md) | | ✅ Hardened | IPC | RecoveryConflictSnapshot | This wait event indicates a **Global MVCC Consistency Barrier**. On a standby, the engine must balance the need to ke... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/RecoveryConflictSnapshot.md) | | ✅ Hardened | IPC | RecoveryConflictTablespace | This wait event indicates a **Physical Resource Deletion Barrier**. Unlike snapshot conflicts (which deal with indivi... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/RecoveryConflictTablespace.md) | | ✅ Hardened | IPC | RecoveryEndCommand | This wait event indicates a **Transition-to-Primary Finalization Barrier**. Administrators use this command to perfor... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/RecoveryEndCommand.md) | | ✅ Hardened | IPC | RecoveryPause | This wait event indicates a **Manual Operational Halt**. Pausing recovery is a diagnostic tool used to "freeze" a sta... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/RecoveryPause.md) | | ✅ Hardened | IPC | ReplicationOriginDrop | This wait event indicates a **Replication Metadata Cleanup Barrier**. Replication origins are used to track progress ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/ReplicationOriginDrop.md) | | ✅ Hardened | IPC | ReplicationSlotDrop | This wait event indicates a **Replication Persistence Cleanup Barrier**. Before a slot can be dropped, the engine mus... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/ReplicationSlotDrop.md) | | ✅ Hardened | IPC | RestoreCommand | This wait event indicates an **External Log Retrieval Delay**. When a standby needs a WAL segment that is no longer i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Recovery/RestoreCommand.md) | | ✅ Hardened | IPC | SafeSnapshot | This wait event indicates a **Mathematical Consistency Barrier**. Serializable Snapshot Isolation (SSI) uses a comple... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/System/SafeSnapshot.md) | | ✅ Hardened | IPC | SyncRep | This wait event indicates that the primary database is stalled by its **Synchronous Replication** requirements. Even ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/System/SyncRep.md) | | ✅ Hardened | IPC | WalReceiverExit | This wait event indicates a **Replication Lifecycle Synchronization Barrier**. It is most common during server shutdo... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/WalReceiverExit.md) | | ✅ Hardened | IPC | WalReceiverWaitStart | This wait event indicates an **Initial Replication Handshake Latency**. Before a standby can resume applying changes,... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/LogicalRep/WalReceiverWaitStart.md) | | ✅ Hardened | IPC | WalSummaryReady | This wait event indicates an **Incremental Backup Pipeline Synchronization Barrier**. Before an incremental backup ca... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/System/WalSummaryReady.md) | | ✅ Hardened | IPC | XactGroupUpdate | This wait event is an artifact of the **Group Commit** optimization. To reduce the overhead of high-frequency commits... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/IPC/Transaction/XactGroupUpdate.md) | | ✅ Hardened | LWLock | AddinShmemInit | This wait event indicates an **Extension Resource Allocation Barrier**. Many Postgres extensions (such as `pg_stat_st... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Shmem/AddinShmemInit.md) | | ✅ Hardened | LWLock | AioUringCompletion | This wait event indicates an **Asynchronous I/O Result Serialization point**. In the `io_uring` model, the kernel wri... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/AIO/AioUringCompletion.md) | | ✅ Hardened | LWLock | AioWorkerSubmissionQueue | This wait event indicates an **I/O Request Serialization point**. It represents the moment where a backend is attempt... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/AIO/AioWorkerSubmissionQueue.md) | | ✅ Hardened | LWLock | AutoFile | This wait event indicates a synchronization stall in the **Persistent Configuration Layer**. The `ALTER SYSTEM` comma... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Config/AutoFile.md) | | ✅ Hardened | LWLock | Autovacuum | This wait event indicates contention on the **Maintenance Scheduling Layer**. To ensure that the engine doesn't excee... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Autovacuum/Autovacuum.md) | | ✅ Hardened | LWLock | AutovacuumSchedule | This wait event indicates contention on the **Maintenance Prioritization Layer**. The Autovacuum Launcher must contin... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Autovacuum/AutovacuumSchedule.md) | | ✅ Hardened | LWLock | BackgroundWorker | This wait event indicates contention on the **Process Orchestration Layer**. To ensure that the engine doesn't exceed... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/BackgroundWorker/BackgroundWorker.md) | | ✅ Hardened | LWLock | BtreeVacuum | This wait event indicates contention on **Index Maintenance**. When `autovacuum` cleans up a table, it must also clea... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/BtreeVacuum.md) | | ✅ Hardened | LWLock | BufferContent | This wait event occurs when a backend is blocked while trying to read or modify the contents of a specific data page ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/BufferContent.md) | | ✅ Hardened | LWLock | BufferMapping | This wait event occurs when a backend process is blocked while searching the **Shared Buffer Hash Table** for a speci... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/BufferMapping.md) | | ✅ Hardened | LWLock | CheckpointerComm | This wait event indicates an **Inter-Process Communication Bottleneck**. Backends communicate with the checkpointer t... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Checkpointer/CheckpointerComm.md) | | ✅ Hardened | LWLock | CommitTs | This wait event indicates contention on the **Transaction Temporal Layer**. Unlike the basic transaction status (CLOG... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/CommitTs/CommitTs.md) | | ✅ Hardened | LWLock | CommitTsBuffer | This wait event indicates contention on a **Specific Timestamp Data Page**. To maintain transactional integrity, the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/CommitTs/CommitTsBuffer.md) | | ✅ Hardened | LWLock | CommitTsSLRU | This wait event indicates contention on the **Temporal Cache Management Layer**. While `CommitTs` handles the actual ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/CommitTs/CommitTsSLRU.md) | | ✅ Hardened | LWLock | ControlFile | This wait event indicates contention on the **Cluster Status Registry**. Every time the engine updates critical globa... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/ControlFile/ControlFile.md) | | ✅ Hardened | LWLock | DSMRegistry | This wait event indicates contention on the **Cross-Process Memory Registry**. Unlike standard shared memory allocate... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/DSMRegistry.md) | | ✅ Hardened | LWLock | DSMRegistryDSA | This wait event indicates contention on the **Registry Memory Management Layer**. While the `DSMRegistry` lock protec... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/DSMRegistryDSA.md) | | ✅ Hardened | LWLock | DSMRegistryEntry | This wait event indicates a **Parallel Resource Access Bottleneck**. Unlike the global `DynamicSharedMemoryControl` (... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/DSMRegistryEntry.md) | | ✅ Hardened | LWLock | DSMRegistryHash | This wait event indicates contention on the **Registry Lookup Layer**. To enable backends to quickly find the shared ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/DSMRegistryHash.md) | | ✅ Hardened | LWLock | DynamicSharedMemoryControl | This wait event indicates a **Parallel Resource Management Bottleneck**. To prevent memory leaks and ensure that work... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/DynamicSharedMemoryControl.md) | | ✅ Hardened | LWLock | InjectionPoint | This wait event indicates a **Diagnostic Coordination Barrier**. Injection points allow developers and testers to int... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/System/InjectionPoint.md) | | ✅ Hardened | LWLock | LockFastPath | This wait event indicates contention on the **Locking Shortcut Registry**. To improve parallel performance, Postgres ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/LockManager/LockFastPath.md) | | ✅ Hardened | LWLock | LockManager | This wait event indicates contention on the **Cluster-Wide Locking Ledger**. While the `LockFastPath` optimization ha... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/LockManager/LockManager.md) | | ✅ Hardened | LWLock | LogicalParallelApplyDSA | This wait event indicates contention on the **Parallel Replication Memory Layer**. In parallel logical apply mode, mu... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalParallelApplyDSA.md) | | ✅ Hardened | LWLock | LogicalParallelApplyHash | This wait event indicates a synchronization stall in **Parallel Replication Coordination**. To ensure that changes fr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalParallelApplyHash.md) | | ✅ Hardened | LWLock | LogicalRepLauncherDSA | This wait event indicates contention on the **Replication Memory Allocator**. To manage the lifecycle of many concurr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalRepLauncherDSA.md) | | ✅ Hardened | LWLock | LogicalRepLauncherHash | This wait event represents a synchronization stall in the **Replication Registry**. The logical replication launcher ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalRepLauncherHash.md) | | ✅ Hardened | LWLock | LogicalRepWorker | This wait event indicates contention on the **Logical Replication Management Layer**. Each worker process (either a s... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/LogicalRepWorker.md) | | ✅ Hardened | LWLock | LogicalRepWorkerDSA | This wait event indicates contention on the **Replication Memory Management Layer**. As a logical replication worker ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalRepWorkerDSA.md) | | ✅ Hardened | LWLock | LogicalRepWorkerHash | This wait event represents a synchronization stall in the **Schema Mapping Registry**. Every time a logical replicati... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/LogicalRepWorkerHash.md) | | ✅ Hardened | LWLock | MultiXactGen | This wait event indicates a **Serialization Bottleneck** in the shared locking system. MultiXacts are the architectur... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactGen.md) | | ✅ Hardened | LWLock | MultiXactMemberBuffer | This wait event indicates a **Shared Lock Metadata Cache Barrier**. While the `IO:MultiXactMemberBuffer` event repres... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactMemberBuffer.md) | | ✅ Hardened | LWLock | MultiXactMemberControlLock | This wait event represents a synchronization stall in the **Shared Locking Registry**. While the "Offset" SLRU tells ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactMemberControlLock.md) | | ✅ Hardened | LWLock | MultiXactMemberSLRU | This wait event indicates contention on the **Shared Lock Membership Cache**. While the "Offset" log tells the engine... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactMemberSLRU.md) | | ✅ Hardened | LWLock | MultiXactOffsetBuffer | This wait event indicates a **Shared Lock Indexing Cache Barrier**. Every time the engine encounters a shared row loc... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactOffsetBuffer.md) | | ✅ Hardened | LWLock | MultiXactOffsetControlLock | This wait event indicates contention on the **MultiXact Mapping Layer**. Every time the engine creates or reads a Mul... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactOffsetControlLock.md) | | ✅ Hardened | LWLock | MultiXactOffsetSLRU | This wait event indicates contention on the **MultiXact Mapping Cache**. Every time the engine encounters a shared ro... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactOffsetSLRU.md) | | ✅ Hardened | LWLock | MultiXactTruncation | This wait event represents a **Log Retention Barrier**. As the cluster advances through MultiXact IDs (MXIDs), old se... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/MultiXact/MultiXactTruncation.md) | | ✅ Hardened | LWLock | NotifyBuffer | This wait event indicates contention on a **Specific Notification Data Page**. In the `LISTEN/NOTIFY` system, message... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifyBuffer.md) | | ✅ Hardened | LWLock | NotifyQueue | This wait event indicates a **Message Dispatch Serialization point**. When a session executes `NOTIFY`, the message i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifyQueue.md) | | ✅ Hardened | LWLock | NotifyQueueControlLock | This wait event indicates contention on the **Notification Management Layer**. This lock is required for any operatio... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifyQueueControlLock.md) | | ✅ Hardened | LWLock | NotifyQueueTail | This wait event indicates a synchronization stall in the **IPC Cleanup Layer**. In the `LISTEN/NOTIFY` system, messag... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifyQueueTail.md) | | ✅ Hardened | LWLock | NotifyQueueTailLock | This wait event indicates contention on the **Notification Cleanup Layer**. In the `LISTEN/NOTIFY` subsystem, Postgre... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifyQueueTailLock.md) | | ✅ Hardened | LWLock | NotifySLRU | This wait event indicates contention on the **Notification Cache Management Layer**. While `NotifyBuffer` handles spe... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Notify/NotifySLRU.md) | | ✅ Hardened | LWLock | OidGen | This wait event indicates a **Serialization Bottleneck** in the object creation layer. Postgres uses a 32-bit OID to ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Catalog/OidGen.md) | | ✅ Hardened | LWLock | OldSnapshotTimeMapping | This wait event indicates contention on the **Snapshot Durability Layer**. The "Old Snapshot Threshold" feature (gove... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/ProcArray/OldSnapshotTimeMapping.md) | | ✅ Hardened | LWLock | ParallelAppend | This wait event indicates contention on the **Parallel Partition Dispatcher**. In a parallel-aware plan targeting a p... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelAppend.md) | | ✅ Hardened | LWLock | ParallelBtreeScan | This wait event indicates a synchronization stall during **Parallel Index Traversal**. In a parallel-aware index scan... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelBtreeScan.md) | | ✅ Hardened | LWLock | ParallelHashJoin | This wait event indicates a synchronization stall during **Parallel Join Orchestration**. A parallel hash join is a c... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelHashJoin.md) | | ✅ Hardened | LWLock | ParallelQuery | This wait event represents a synchronization stall at the **Query Execution Boundary**. It is the primary lock used t... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelQuery.md) | | ✅ Hardened | LWLock | ParallelQueryDSA | This wait event indicates contention on the **Global Parallel Management Layer**. While `PerSessionDSA` manages the d... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelQueryDSA.md) | | ✅ Hardened | LWLock | ParallelVacuumDSA | This wait event indicates contention on the **Maintenance Memory Allocator**. Parallel vacuum allows multiple worker ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/ParallelVacuumDSA.md) | | ✅ Hardened | LWLock | PerSessionDSA | This wait event indicates contention on the **Session-Level Shared Memory Allocator**. While core shared memory is pr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PerSessionDSA.md) | | ✅ Hardened | LWLock | PerSessionDSL | This wait event indicates contention on the **Session-Level Memory Management Layer**. When a parallel query starts, ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PerSessionDSL.md) | | ✅ Hardened | LWLock | PerSessionRecordType | This wait event represents a synchronization stall in **Parallel Metadata Sharing**. When a query defines a temporary... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PerSessionRecordType.md) | | ✅ Hardened | LWLock | PerSessionRecordTypmod | This wait event indicates contention on the **Parallel Type Management Layer**. Because parallel workers operate in s... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PerSessionRecordTypmod.md) | | ✅ Hardened | LWLock | PerXactPredicateList | This wait event indicates contention on the **Parallel SSI Coordination Layer**. When a serializable transaction laun... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PerXactPredicateList.md) | | ✅ Hardened | LWLock | PgStatsDSA | This wait event represents a synchronization stall in **Observability Memory Management**. While the `PgStatsHash` lo... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PgStatsDSA.md) | | ✅ Hardened | LWLock | PgStatsData | This wait event represents a synchronization stall in the **Observability Control Layer**. While other stats locks ha... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PgStatsData.md) | | ✅ Hardened | LWLock | PgStatsHash | This wait event represents a synchronization stall in the **Observability Layer**. In modern Postgres versions, the s... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Parallel/PgStatsHash.md) | | ✅ Hardened | LWLock | PredicateLockManager | This wait event indicates an **SSI Coordination Bottleneck**. Unlike standard locks (which protect physical rows), pr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SSI/PredicateLockManager.md) | | ✅ Hardened | LWLock | ProcArray | This wait event indicates contention on the **Global Visibility Coordinator**. Every time a query starts, it must tak... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/ProcArray/ProcArray.md) | | ✅ Hardened | LWLock | RelCacheInit | This wait event indicates contention on the **Backend Bootstrap Layer**. To avoid the expensive overhead of scanning ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Catalog/RelCacheInit.md) | | ✅ Hardened | LWLock | RelationMapping | This wait event indicates contention on the **Physical Identity Layer**. While most relations store their file identi... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Catalog/RelationMapping.md) | | ✅ Hardened | LWLock | ReplicationOrigin | This wait event indicates contention on the **Logical Source Tracking Layer**. For every incoming transaction, a subs... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/ReplicationOrigin.md) | | ✅ Hardened | LWLock | ReplicationOriginState | This wait event indicates a **Replication Progress Serialization point**. While `ReplicationOrigin` locks protect the... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/ReplicationOriginState.md) | | ✅ Hardened | LWLock | ReplicationSlotAllocation | This wait event indicates contention on the **Replication Resource Pool**. Postgres has a fixed number of replication... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/ReplicationSlotAllocation.md) | | ✅ Hardened | LWLock | ReplicationSlotControl | This wait event indicates contention on the **Replication Orchestration Layer**. To ensure that replication progress ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/ReplicationSlotControl.md) | | ✅ Hardened | LWLock | ReplicationSlotIO | This wait event indicates that a process is blocked while performing **Replication Slot Bookkeeping**. Each time a st... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/ReplicationSlotIO.md) | | ✅ Hardened | LWLock | SInvalRead | This wait event indicates a synchronization stall in the **Cache Consistency System**. Because every Postgres process... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Catalog/SInvalRead.md) | | ✅ Hardened | LWLock | SInvalWrite | This wait event indicates a **Metadata Broadcast Bottleneck**. Whenever a database object is created, altered, or dro... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Catalog/SInvalWrite.md) | | ✅ Hardened | LWLock | SerialBuffer | This wait event indicates a **Serializable Metadata Access Bottleneck**. The serial log (stored in `pg_serial/`) is u... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Serial/SerialBuffer.md) | | ✅ Hardened | LWLock | SerialControl | This wait event indicates an **SSI Lifecycle Management Bottleneck**. While `PredicateLockManager` handles the actual... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SSI/SerialControl.md) | | ✅ Hardened | LWLock | SerialSLRU | This wait event indicates a **Serializable Metadata Persistence Bottleneck**. While `SerialBuffer` protects individua... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Serial/SerialSLRU.md) | | ✅ Hardened | LWLock | SerializableFinishedList | This wait event indicates an **SSI Conflict Post-Processing Bottleneck**. Even after a `SERIALIZABLE` transaction com... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SSI/SerializableFinishedList.md) | | ✅ Hardened | LWLock | SerializablePredicateList | This wait event indicates an **SSI Session Metadata Access Barrier**. Every `SERIALIZABLE` transaction maintains a pr... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SSI/SerializablePredicateList.md) | | ✅ Hardened | LWLock | SerializableXactHash | This wait event indicates an **SSI Identity Discovery Bottleneck**. To detect conflicts between sessions, Postgres mu... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SSI/SerializableXactHash.md) | | ✅ Hardened | LWLock | SharedTidBitmap | This wait event indicates contention on the **Parallel Scan Results**. In a parallel bitmap scan, the leader process ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/SharedTidBitmap.md) | | ✅ Hardened | LWLock | SharedTupleStore | This wait event indicates contention on the **Cross-Worker Data Exchange Layer**. When a query requires multiple para... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Buffers/SharedTupleStore.md) | | ✅ Hardened | LWLock | ShmemIndex | This wait event indicates contention on the **Resource Allocation Layer** of shared memory. To ensure that different ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Shmem/ShmemIndex.md) | | ✅ Hardened | LWLock | SubtransBuffer | This wait event indicates contention on a **Specific Subtransaction Mapping Page**. The `pg_subtrans` log is a critic... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Subtrans/SubtransBuffer.md) | | ✅ Hardened | LWLock | SubtransSLRU | This wait event indicates contention on the **Sub-transaction Mapping Layer**. Because Postgres uses sub-transactions... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Subtrans/SubtransSLRU.md) | | ✅ Hardened | LWLock | SyncRep | This wait event indicates a **Durability Metadata Access Bottleneck**. While the `IPC:SyncRep` wait event represents ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Replication/SyncRep.md) | | ✅ Hardened | LWLock | SyncScan | This wait event indicates contention on the **Scan Coordination Layer**. Synchronized scans (governed by `synchronize... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/SeqScan/SyncScan.md) | | ✅ Hardened | LWLock | TablespaceCreate | This wait event indicates a **Physical Infrastructure Serialization Point**. Because tablespaces map database objects... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Tablespace/TablespaceCreate.md) | | ✅ Hardened | LWLock | TwoPhaseState | This wait event indicates contention on the **Distributed Transaction Registry**. When an application uses `PREPARE T... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Xact/TwoPhaseState.md) | | ✅ Hardened | LWLock | WALBufMapping | This wait event indicates contention on the **WAL Cache Management Layer**. Before any transaction record can be inse... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/WAL/WALBufMapping.md) | | ✅ Hardened | LWLock | WALInsert | This wait event indicates a **Serialization Pinch Point** at the start of the durability cycle. Before any backend ca... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/WAL/WALInsert.md) | | ✅ Hardened | LWLock | WALSummarizer | This wait event indicates contention on the **Incremental Backup Layer**. Introduced in Postgres 17, the WAL Summariz... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/WAL/WALSummarizer.md) | | ✅ Hardened | LWLock | WALWrite | This wait event indicates a **Physical Durability Bottleneck**. While `WALInsert` handles the in-memory sequencing of... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/WAL/WALWrite.md) | | ✅ Hardened | LWLock | WaitEvent | This wait event indicates contention on the **Observability Registration Layer**. While core Postgres wait events hav... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Observability/WaitEvent.md) | | ✅ Hardened | LWLock | WaitEventCustom | This wait event indicates contention on the **Observability Extension Layer**. To maintain high resolution in perform... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Observability/WaitEventCustom.md) | | ✅ Hardened | LWLock | WrapLimitsVacuum | This wait event indicates contention on the **Cluster Safety Layer**. To prevent data corruption caused by Transactio... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Autovacuum/WrapLimitsVacuum.md) | | ✅ Hardened | LWLock | XLogBuffer | This wait event indicates contention on the **Transaction Log Caching Layer**. To improve performance, Postgres does ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/WAL/XLogBuffer.md) | | ✅ Hardened | LWLock | XactBuffer | This wait event indicates contention on the **Transaction Visibility Layer**. The Xact SLRU (historically called the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Xact/XactBuffer.md) | | ✅ Hardened | LWLock | XactSLRU | This wait event indicates contention on the **Transaction Cache Management Layer**. While `XactBuffer` handles specif... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Xact/XactSLRU.md) | | ✅ Hardened | LWLock | XactTruncation | This wait event represents a **Transaction History Cleanup Barrier**. As Transaction IDs (XIDs) advance, the engine n... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Xact/XactTruncation.md) | | ✅ Hardened | LWLock | XidGen | This wait event indicates a **Serialization Bottleneck** at the heart of the engine's transaction system. Every backe... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/LWLock/Xact/XidGen.md) | | ✅ Hardened | Lock | advisory | This wait event indicates an **Application-Level Synchronization Barrier**. Advisory locks are a feature that allows ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/advisory.md) | | ✅ Hardened | Lock | applytransaction | This wait event indicates a **Replication Ordering Barrier**. In some replication configurations (specifically those ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/applytransaction.md) | | ✅ Hardened | Lock | extend | This wait event indicates a **File Growth Serialization point**. To prevent multiple processes from corrupting a file... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/extend.md) | | ✅ Hardened | Lock | frozenid | This wait event indicates a **Replication Identity Consistency Barrier**. It is used during complex replication scena... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/frozenid.md) | | ✅ Hardened | Lock | object | This wait event indicates a **General Metadata Access Barrier**. While `relation` locks cover tables and indexes, `ob... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/object.md) | | ✅ Hardened | Lock | page | This wait event indicates a **Physical Data Page Contention Barrier**. While `tuple` locks protect individual rows, `... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/page.md) | | ✅ Hardened | Lock | relation | This wait event indicates a blockade on a database object, such as a table or index. Unlike lightweight locks (LWLock... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/relation.md) | | ✅ Hardened | Lock | spectoken | This wait event indicates an **Optimistic Concurrency Barrier**. To handle the `ON CONFLICT` clause efficiently, Post... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/spectoken.md) | | ✅ Hardened | Lock | transactionid | This wait event is the definitive marker of **Row-Level Contention**. When two transactions attempt to modify the sam... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/transactionid.md) | | ✅ Hardened | Lock | tuple | This wait event indicates a **Direct Data Contention Barrier**. While most row-level locking in Postgres is handled i... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/tuple.md) | | ✅ Hardened | Lock | userlock | This wait event indicates an **Application-Layer Coordination Barrier**. User locks were the precursor to modern `adv... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/userlock.md) | | ✅ Hardened | Lock | virtualxid | This wait event indicates a **Read-Only Transaction Synchronization Barrier**. To save on the limited 32-bit transact... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Lock/virtualxid.md) | | ✅ Hardened | Timeout | BaseBackupThrottle | This wait event indicates an **Intentional I/O Governor**. To prevent a massive backup operation from saturating the ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/BaseBackupThrottle.md) | | ✅ Hardened | Timeout | CheckpointWriteDelay | This wait event indicates **I/O Smoothing Architecture**. To prevent a "Checkpoint Spike"—where the storage subsystem... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/CheckpointWriteDelay.md) | | ✅ Hardened | Timeout | CheckpointerWriteDelay | This wait event represents the **Paced Flushing** of the buffer cache. To prevent a "checkpoint spike" from saturatin... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/CheckpointerWriteDelay.md) | | ✅ Hardened | Timeout | PgSleep | This wait event indicates an **Explicit Query Suspension**. Unlike other timeouts which are triggered by the engine's... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/PgSleep.md) | | ✅ Hardened | Timeout | RecoveryApplyDelay | This wait event indicates an **Architectural Time-Lag**. Standby servers are often configured with a delay (governed ... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/RecoveryApplyDelay.md) | | ✅ Hardened | Timeout | RecoveryRetrieveRetryInterval | This wait event indicates a **Transaction Log Underflow**. During continuous recovery, the startup process must const... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/RecoveryRetrieveRetryInterval.md) | | ✅ Hardened | Timeout | RegisterSyncRequest | This wait event indicates a **Durability Pipeline Logjam**. To ensure transactional consistency without blocking ever... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/RegisterSyncRequest.md) | | ✅ Hardened | Timeout | SpinDelay | This wait event indicates **Ultra-High Concurrency Contention**. Spinlocks are the most primitive and fastest synchro... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/SpinDelay.md) | | ✅ Hardened | Timeout | VacuumDelay | This wait event represents the **Polite Throttling** of the maintenance system. To prevent a massive vacuum operation... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/VacuumDelay.md) | | ✅ Hardened | Timeout | VacuumTruncate | This wait event indicates a **Physical File Shrinkage Barrier**. After the `VACUUM` process has removed dead tuples a... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/VacuumTruncate.md) | | ✅ Hardened | Timeout | WalSummarizerError | This wait event indicates a **Self-Healing Recovery Delay**. Introduced in Postgres 17 to support incremental backups... | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/Timeout/WalSummarizerError.md) | | ⏳ Draft | visual_coverage_audit.md | visual_coverage_audit | [No Description] | [Link](file:///Users/aesakamar/Code/LearnYouAPostgres/Workloads/visual_coverage_audit.md) |