![[wl_io_buffercontent.png|256]]
- **Description**: Indicates that a session is waiting to either read or write a
data page that is already in memory, but another session currently holds a
lock on that page. This reflects contention for accessing shared memory
buffers.
- **Operations**:
- [[IndexScan]]
- [[FunctionScan]]
- [[Result]]
- [[SubqueryScan]]
- [[Materialize]]
- [[TidScan]]
- [[HashJoin]]
- [[SeqScan]]
- [[TableFuncScan]]
- [[ValuesScan]]
- [[CTEScan]]
- [[BitmapIndexScan]]
- [[MergeJoin]]
- [[BitmapAndBitmapOr]]
- [[WindowAgg]]
- [[ProjectSet]]
- [[RecursiveUnion]]
- [[BitmapHeapScan]]
- [[Aggregate]]
- [[SetOp]]
- [[NestedLoop]]
- [[IndexOnlyScan]]
- [[Limit]]
- [[ModifyTable]]
- [[MergeAppend]]
- [[Sort]]
- [[SampleScan]]
- [[Unique]]
- [[CustomScanForeignScan]]
- **Resources**: [[Memory]], [[CPU]]