28.2. The Statistics Collector (original) (raw)

Wait Event Type	Wait Event Name	Description
LWLock	ShmemIndexLock	Waiting to find or allocate space in shared memory.
OidGenLock	Waiting to allocate or assign an OID.
XidGenLock	Waiting to allocate or assign a transaction id.
ProcArrayLock	Waiting to get a snapshot or clearing a transaction id at transaction end.
SInvalReadLock	Waiting to retrieve or remove messages from shared invalidation queue.
SInvalWriteLock	Waiting to add a message in shared invalidation queue.
WALBufMappingLock	Waiting to replace a page in WAL buffers.
WALWriteLock	Waiting for WAL buffers to be written to disk.
ControlFileLock	Waiting to read or update the control file or creation of a new WAL file.
CheckpointLock	Waiting to perform checkpoint.
CLogControlLock	Waiting to read or update transaction status.
SubtransControlLock	Waiting to read or update sub-transaction information.
MultiXactGenLock	Waiting to read or update shared multixact state.
MultiXactOffsetControlLock	Waiting to read or update multixact offset mappings.
MultiXactMemberControlLock	Waiting to read or update multixact member mappings.
RelCacheInitLock	Waiting to read or write relation cache initialization file.
CheckpointerCommLock	Waiting to manage fsync requests.
TwoPhaseStateLock	Waiting to read or update the state of prepared transactions.
TablespaceCreateLock	Waiting to create or drop the tablespace.
BtreeVacuumLock	Waiting to read or update vacuum-related information for a B-tree index.
AddinShmemInitLock	Waiting to manage space allocation in shared memory.
AutovacuumLock	Autovacuum worker or launcher waiting to update or read the current state of autovacuum workers.
AutovacuumScheduleLock	Waiting to ensure that the table it has selected for a vacuum still needs vacuuming.
SyncScanLock	Waiting to get the start location of a scan on a table for synchronized scans.
RelationMappingLock	Waiting to update the relation map file used to store catalog to filenode mapping.
AsyncCtlLock	Waiting to read or update shared notification state.
AsyncQueueLock	Waiting to read or update notification messages.
SerializableXactHashLock	Waiting to retrieve or store information about serializable transactions.
SerializableFinishedListLock	Waiting to access the list of finished serializable transactions.
SerializablePredicateLockListLock	Waiting to perform an operation on a list of locks held by serializable transactions.
OldSerXidLock	Waiting to read or record conflicting serializable transactions.
SyncRepLock	Waiting to read or update information about synchronous replicas.
BackgroundWorkerLock	Waiting to read or update background worker state.
DynamicSharedMemoryControlLock	Waiting to read or update dynamic shared memory state.
AutoFileLock	Waiting to update the postgresql.auto.conf file.
ReplicationSlotAllocationLock	Waiting to allocate or free a replication slot.
ReplicationSlotControlLock	Waiting to read or update replication slot state.
CommitTsControlLock	Waiting to read or update transaction commit timestamps.
CommitTsLock	Waiting to read or update the last value set for the transaction timestamp.
ReplicationOriginLock	Waiting to setup, drop or use replication origin.
MultiXactTruncationLock	Waiting to read or truncate multixact information.
OldSnapshotTimeMapLock	Waiting to read or update old snapshot control information.
BackendRandomLock	Waiting to generate a random number.
LogicalRepWorkerLock	Waiting for action on logical replication worker to finish.
CLogTruncationLock	Waiting to execute txid_status or update the oldest transaction id available to it.
WrapLimitsVacuumLock	Waiting to update limits on transaction id and multixact consumption.
NotifyQueueTailLock	Waiting to update limit on notification message storage.
clog	Waiting for I/O on a clog (transaction status) buffer.
commit_timestamp	Waiting for I/O on commit timestamp buffer.
subtrans	Waiting for I/O a subtransaction buffer.
multixact_offset	Waiting for I/O on a multixact offset buffer.
multixact_member	Waiting for I/O on a multixact_member buffer.
async	Waiting for I/O on an async (notify) buffer.
oldserxid	Waiting for I/O on an oldserxid buffer.
wal_insert	Waiting to insert WAL into a memory buffer.
buffer_content	Waiting to read or write a data page in memory.
buffer_io	Waiting for I/O on a data page.
replication_origin	Waiting to read or update the replication progress.
replication_slot_io	Waiting for I/O on a replication slot.
proc	Waiting to read or update the fast-path lock information.
buffer_mapping	Waiting to associate a data block with a buffer in the buffer pool.
lock_manager	Waiting to add or examine locks for backends, or waiting to join or exit a locking group (used by parallel query).
predicate_lock_manager	Waiting to add or examine predicate lock information.
parallel_query_dsa	Waiting for parallel query dynamic shared memory allocation lock.
tbm	Waiting for TBM shared iterator lock.
parallel_append	Waiting to choose the next subplan during Parallel Append plan execution.
parallel_hash_join	Waiting to allocate or exchange a chunk of memory or update counters during Parallel Hash plan execution.
Lock	relation	Waiting to acquire a lock on a relation.
extend	Waiting to extend a relation.
frozenid	Waiting to update pg_database.datfrozenxid and pg_database.datminmxid.
page	Waiting to acquire a lock on page of a relation.
tuple	Waiting to acquire a lock on a tuple.
transactionid	Waiting for a transaction to finish.
virtualxid	Waiting to acquire a virtual xid lock.
speculative token	Waiting to acquire a speculative insertion lock.
object	Waiting to acquire a lock on a non-relation database object.
userlock	Waiting to acquire a user lock.
advisory	Waiting to acquire an advisory user lock.
BufferPin	BufferPin	Waiting to acquire a pin on a buffer.
Activity	ArchiverMain	Waiting in main loop of the archiver process.
AutoVacuumMain	Waiting in main loop of autovacuum launcher process.
BgWriterHibernate	Waiting in background writer process, hibernating.
BgWriterMain	Waiting in main loop of background writer process background worker.
CheckpointerMain	Waiting in main loop of checkpointer process.
LogicalApplyMain	Waiting in main loop of logical apply process.
LogicalLauncherMain	Waiting in main loop of logical launcher process.
PgStatMain	Waiting in main loop of the statistics collector process.
RecoveryWalAll	Waiting for WAL from a stream at recovery.
RecoveryWalStream	Waiting when WAL data is not available from any kind of sources (local, archive or stream) before trying again to retrieve WAL data, at recovery.
SysLoggerMain	Waiting in main loop of syslogger process.
WalReceiverMain	Waiting in main loop of WAL receiver process.
WalSenderMain	Waiting in main loop of WAL sender process.
WalWriterMain	Waiting in main loop of WAL writer process.
Client	ClientRead	Waiting to read data from the client.
ClientWrite	Waiting to write data to the client.
LibPQWalReceiverConnect	Waiting in WAL receiver to establish connection to remote server.
LibPQWalReceiverReceive	Waiting in WAL receiver to receive data from remote server.
SSLOpenServer	Waiting for SSL while attempting connection.
WalReceiverWaitStart	Waiting for startup process to send initial data for streaming replication.
WalSenderWaitForWAL	Waiting for WAL to be flushed in WAL sender process.
WalSenderWriteData	Waiting for any activity when processing replies from WAL receiver in WAL sender process.
Extension	Extension	Waiting in an extension.
IPC	BgWorkerShutdown	Waiting for background worker to shut down.
BgWorkerStartup	Waiting for background worker to start up.
BtreePage	Waiting for the page number needed to continue a parallel B-tree scan to become available.
ClogGroupUpdate	Waiting for group leader to update transaction status at transaction end.
ExecuteGather	Waiting for activity from child process when executing Gather node.
Hash/Batch/Allocating	Waiting for an elected Parallel Hash participant to allocate a hash table.
Hash/Batch/Electing	Electing a Parallel Hash participant to allocate a hash table.
Hash/Batch/Loading	Waiting for other Parallel Hash participants to finish loading a hash table.
Hash/Build/Allocating	Waiting for an elected Parallel Hash participant to allocate the initial hash table.
Hash/Build/Electing	Electing a Parallel Hash participant to allocate the initial hash table.
Hash/Build/HashingInner	Waiting for other Parallel Hash participants to finish hashing the inner relation.
Hash/Build/HashingOuter	Waiting for other Parallel Hash participants to finish partitioning the outer relation.
Hash/GrowBatches/Allocating	Waiting for an elected Parallel Hash participant to allocate more batches.
Hash/GrowBatches/Deciding	Electing a Parallel Hash participant to decide on future batch growth.
Hash/GrowBatches/Electing	Electing a Parallel Hash participant to allocate more batches.
Hash/GrowBatches/Finishing	Waiting for an elected Parallel Hash participant to decide on future batch growth.
Hash/GrowBatches/Repartitioning	Waiting for other Parallel Hash participants to finishing repartitioning.
Hash/GrowBuckets/Allocating	Waiting for an elected Parallel Hash participant to finish allocating more buckets.
Hash/GrowBuckets/Electing	Electing a Parallel Hash participant to allocate more buckets.
Hash/GrowBuckets/Reinserting	Waiting for other Parallel Hash participants to finish inserting tuples into new buckets.
LogicalSyncData	Waiting for logical replication remote server to send data for initial table synchronization.
LogicalSyncStateChange	Waiting for logical replication remote server to change state.
MessageQueueInternal	Waiting for other process to be attached in shared message queue.
MessageQueuePutMessage	Waiting to write a protocol message to a shared message queue.
MessageQueueReceive	Waiting to receive bytes from a shared message queue.
MessageQueueSend	Waiting to send bytes to a shared message queue.
ParallelBitmapScan	Waiting for parallel bitmap scan to become initialized.
ParallelCreateIndexScan	Waiting for parallel CREATE INDEX workers to finish heap scan.
ParallelFinish	Waiting for parallel workers to finish computing.
ProcArrayGroupUpdate	Waiting for group leader to clear transaction id at transaction end.
ReplicationOriginDrop	Waiting for a replication origin to become inactive to be dropped.
ReplicationSlotDrop	Waiting for a replication slot to become inactive to be dropped.
SafeSnapshot	Waiting for a snapshot for a READ ONLY DEFERRABLE transaction.
SyncRep	Waiting for confirmation from remote server during synchronous replication.
Timeout	BaseBackupThrottle	Waiting during base backup when throttling activity.
PgSleep	Waiting in process that called pg_sleep.
RecoveryApplyDelay	Waiting to apply WAL at recovery because it is delayed.
IO	BufFileRead	Waiting for a read from a buffered file.
BufFileWrite	Waiting for a write to a buffered file.
ControlFileRead	Waiting for a read from the control file.
ControlFileSync	Waiting for the control file to reach durable storage.
ControlFileSyncUpdate	Waiting for an update to the control file to reach durable storage.
ControlFileWrite	Waiting for a write to the control file.
ControlFileWriteUpdate	Waiting for a write to update the control file.
CopyFileRead	Waiting for a read during a file copy operation.
CopyFileWrite	Waiting for a write during a file copy operation.
DataFileExtend	Waiting for a relation data file to be extended.
DataFileFlush	Waiting for a relation data file to reach durable storage.
DataFileImmediateSync	Waiting for an immediate synchronization of a relation data file to durable storage.
DataFilePrefetch	Waiting for an asynchronous prefetch from a relation data file.
DataFileRead	Waiting for a read from a relation data file.
DataFileSync	Waiting for changes to a relation data file to reach durable storage.
DataFileTruncate	Waiting for a relation data file to be truncated.
DataFileWrite	Waiting for a write to a relation data file.
DSMFillZeroWrite	Waiting to write zero bytes to a dynamic shared memory backing file.
LockFileAddToDataDirRead	Waiting for a read while adding a line to the data directory lock file.
LockFileAddToDataDirSync	Waiting for data to reach durable storage while adding a line to the data directory lock file.
LockFileAddToDataDirWrite	Waiting for a write while adding a line to the data directory lock file.
LockFileCreateRead	Waiting to read while creating the data directory lock file.
LockFileCreateSync	Waiting for data to reach durable storage while creating the data directory lock file.
LockFileCreateWrite	Waiting for a write while creating the data directory lock file.
LockFileReCheckDataDirRead	Waiting for a read during recheck of the data directory lock file.
LogicalRewriteCheckpointSync	Waiting for logical rewrite mappings to reach durable storage during a checkpoint.
LogicalRewriteMappingSync	Waiting for mapping data to reach durable storage during a logical rewrite.
LogicalRewriteMappingWrite	Waiting for a write of mapping data during a logical rewrite.
LogicalRewriteSync	Waiting for logical rewrite mappings to reach durable storage.
LogicalRewriteTruncate	Waiting for truncate of mapping data during a logical rewrite.
LogicalRewriteWrite	Waiting for a write of logical rewrite mappings.
RelationMapRead	Waiting for a read of the relation map file.
RelationMapSync	Waiting for the relation map file to reach durable storage.
RelationMapWrite	Waiting for a write to the relation map file.
ReorderBufferRead	Waiting for a read during reorder buffer management.
ReorderBufferWrite	Waiting for a write during reorder buffer management.
ReorderLogicalMappingRead	Waiting for a read of a logical mapping during reorder buffer management.
ReplicationSlotRead	Waiting for a read from a replication slot control file.
ReplicationSlotRestoreSync	Waiting for a replication slot control file to reach durable storage while restoring it to memory.
ReplicationSlotSync	Waiting for a replication slot control file to reach durable storage.
ReplicationSlotWrite	Waiting for a write to a replication slot control file.
SLRUFlushSync	Waiting for SLRU data to reach durable storage during a checkpoint or database shutdown.
SLRURead	Waiting for a read of an SLRU page.
SLRUSync	Waiting for SLRU data to reach durable storage following a page write.
SLRUWrite	Waiting for a write of an SLRU page.
SnapbuildRead	Waiting for a read of a serialized historical catalog snapshot.
SnapbuildSync	Waiting for a serialized historical catalog snapshot to reach durable storage.
SnapbuildWrite	Waiting for a write of a serialized historical catalog snapshot.
TimelineHistoryFileSync	Waiting for a timeline history file received via streaming replication to reach durable storage.
TimelineHistoryFileWrite	Waiting for a write of a timeline history file received via streaming replication.
TimelineHistoryRead	Waiting for a read of a timeline history file.
TimelineHistorySync	Waiting for a newly created timeline history file to reach durable storage.
TimelineHistoryWrite	Waiting for a write of a newly created timeline history file.
TwophaseFileRead	Waiting for a read of a two phase state file.
TwophaseFileSync	Waiting for a two phase state file to reach durable storage.
TwophaseFileWrite	Waiting for a write of a two phase state file.
WALBootstrapSync	Waiting for WAL to reach durable storage during bootstrapping.
WALBootstrapWrite	Waiting for a write of a WAL page during bootstrapping.
WALCopyRead	Waiting for a read when creating a new WAL segment by copying an existing one.
WALCopySync	Waiting a new WAL segment created by copying an existing one to reach durable storage.
WALCopyWrite	Waiting for a write when creating a new WAL segment by copying an existing one.
WALInitSync	Waiting for a newly initialized WAL file to reach durable storage.
WALInitWrite	Waiting for a write while initializing a new WAL file.
WALRead	Waiting for a read from a WAL file.
WALSenderTimelineHistoryRead	Waiting for a read from a timeline history file during walsender timeline command.
WALSyncMethodAssign	Waiting for data to reach durable storage while assigning WAL sync method.
WALWrite	Waiting for a write to a WAL file.