# Parallel Coordination (The Elephant Yell) When one elephant isn't enough, we hire a whole herd. **Parallelism** in Postgres allows the Head Chef to divide a large task into smaller ones and distribute them across multiple background workers. To keep everything in sync, the elephants must yell back and forth across the room, waiting for each other to finish their specific task. ### Parallel Coordination ![[AppendReady]] ![[ExecuteGather]] ![[ParallelBitmapScan]] ![[ParallelCreateIndexScan]] ![[ParallelFinish]] ![[SharedTidBitmap]] ![[SharedTupleStore]] ### Memory Management for Parallel Workers ![[Workloads/IO/DSM/DSMAllocate]] ![[DynamicSharedMemoryControl]]