Waiting for background worker to start up. Waiting to access the sub-transaction SLRU cache. In rows about other sessions, many columns will be null. It works like this: Waiting to read or write relation cache initialization file. pg_stat_get_snapshot_timestamp () timestamp with time zone, Returns the timestamp of the current statistics snapshot, or NULL if no statistics snapshot has been taken. Restrict the maximum number of connections to the database as a best practice. Waiting to read or update the fast-path lock information. OID of this database, or 0 for objects belonging to a shared relation. The function pg_stat_get_backend_idset provides a convenient way to generate one row for each active backend for invoking these functions. a page) has to be retrieved outside the shared buffer pool. Number of WAL files that have been successfully archived, Name of the WAL file most recently successfully archived, last_archived_time timestamp with time zone, Time of the most recent successful archive operation, Number of failed attempts for archiving WAL files, Name of the WAL file of the most recent failed archival operation, last_failed_time timestamp with time zone, Time of the most recent failed archival operation. Waiting for a write of a timeline history file received via streaming replication. In particular, when the standby has caught up completely, pg_stat_replication shows the time taken to write, flush and replay the most recent reported WAL location rather than zero as some users might expect. Waiting to add a message to the shared catalog invalidation queue. Note, however, that the existence of a session and its general properties such as its sessions user and database are visible to all users. Waiting for parallel workers to finish computing. The type of event for which the backend is waiting, if any; otherwise NULL. True if GSSAPI authentication was used for this connection. Topics Relevant engine versions Context Causes Actions Relevant engine versions You can split your The parameter track_activities enables monitoring of the current command being executed by any server process. This event type indicates a process waiting for activity in its main processing loop. Waiting for truncate of mapping data during a logical rewrite. Waiting to associate a data block with a buffer in the buffer pool. But access to that shared memory requires the protection of light-weight locks, which should last for only nanoseconds or microseconds while the memory access is actually occuring. Pointers to free buffers and to the next victim are protected by one buffer strategy lock spinlock. Waiting for recovery conflict resolution for dropping a tablespace. The reported lag times are not predictions of how long it will take for the standby to catch up with the sending server assuming the current rate of replay. Waiting to select the starting location of a synchronized table scan. The pg_stat_database_conflicts view will contain one row per database, showing database-wide statistics about query cancels occurring due to conflicts with recovery on standby servers. The server process is waiting for an I/O operation to complete. active: The backend is executing a query. Possible types are autovacuum launcher, autovacuum worker, logical replication launcher, logical replication worker, parallel worker, background writer, client backend, checkpointer, archiver, startup, walreceiver, walsender and walwriter. Simple test for lock_waits log messages. The argument can be one of CommitTs, MultiXactMember, MultiXactOffset, Notify, Serial, Subtrans, or Xact to reset the counters for only that entry. Waiting for SLRU data to reach durable storage following a page write. IP address of the client connected to this backend. Waiting for a write to the relation map file. Waiting for a write of mapping data during a logical rewrite. Possible values are: Activity status of the WAL receiver process, First write-ahead log location used when WAL receiver is started, First timeline number used when WAL receiver is started, Last write-ahead log location already received and flushed to disk, the initial value of this field being the first log location used when WAL receiver is started, Timeline number of last write-ahead log location received and flushed to disk, the initial value of this field being the timeline number of the first log location used when WAL receiver is started, Send time of last message received from origin WAL sender, Receipt time of last message received from origin WAL sender, Last write-ahead log location reported to origin WAL sender, Time of last write-ahead log location reported to origin WAL sender, Replication slot name used by this WAL receiver. postgres 26 Heap_Insert replication_slot_io: Waiting for I/O on a replication slot. The function pg_stat_get_backend_idset provides a convenient way to generate one row for each active backend for invoking these functions. This field is truncated if the DN field is longer than NAMEDATALEN (64 characters in a standard build). ; Ensure that filesystem journaling is turned off for data files and WAL files. Activity status of the WAL receiver process, First write-ahead log location used when WAL receiver is started, First timeline number used when WAL receiver is started. Additional Statistics Functions. Priority of this standby server for being chosen as the synchronous standby in a priority-based synchronous replication. 214 . However, current-query information collected by track_activities is always up-to-date. Best practices for Amazon RDS for PostgreSQL cross-Region read replicas pg_stat_reset_subscription_stats ( oid ) void. catchup: This WAL sender's connected standby is catching up with the primary. The lag times reported in the pg_stat_replication view are measurements of the time taken for recent WAL to be written, flushed and replayed and for the sender to know about it. Autovacuum worker or launcher waiting to update or read the current state of autovacuum workers. See Section30.5 for more information about the internal WAL function issue_xlog_fsync. This and other streaming counters for this slot can be used to tune logical_decoding_work_mem. Waiting for the version file to be written while creating a database. wait_event will identify the specific wait point. Identifier of this backend's most recent query. Users interested in obtaining more detailed information on PostgreSQL I/O behavior are advised to use the PostgreSQL statistics views in combination with operating system utilities that allow insight into the kernel's handling of I/O. Waiting to access the list of predicate locks held by the current serializable transaction during a parallel query. Waiting to elect a Parallel Hash participant to allocate more batches. Postgres 10.3: SELECT queries hang for hours - Stack Overflow The functions for per-function statistics take a function OID. Buffer pin waits can be protracted if another process holds an open cursor that last read data from the buffer in question. See, One row per connection (regular and replication), showing information about SSL used on this connection. Similarly, information about the current queries of all sessions is collected when any such information is first requested within a transaction, and the same information will be displayed throughout the transaction. Waiting in main loop of WAL sender process. Connection string used by this WAL receiver, with security-sensitive fields obfuscated. Waiting to add or examine locks for backends, or waiting to join or exit a locking group (used by parallel query). Waiting for a read while adding a line to the data directory lock file. If enabled, calls to user-defined functions and the total time spent in each one are counted as well. streaming: This WAL sender is streaming changes after its connected standby server has caught up with the primary. 105 #define BUFFER_MAPPING_LWLOCK_OFFSET NUM_INDIVIDUAL_LWLOCKS. lock_manager This facility is independent of the cumulative statistics system. Returns the set of currently active backend ID numbers (from 1 to the number of active backends). Resets statistics for a single function in the current database to zero. Waiting for a replication slot control file to reach durable storage while restoring it to memory. Waiting to access the shared per-process data structures (typically, to get a snapshot or report a session's transaction ID). sync: This standby server is synchronous. The pg_stat_all_indexes view will contain one row for each index in the current database, showing statistics about accesses to that specific index. Thus, the server expects something to happen that is independent of its internal processes. The new locking scheme avoids grabbing system-wide exclusive locks in common code paths. Waiting for a write while initializing a new WAL file. Number of in-progress transactions streamed to the decoding output plugin after the memory used by logical decoding to decode changes from WAL for this slot has exceeded logical_decoding_work_mem. DN of the issuer of the client certificate, or NULL if no client certificate was supplied or if SSL is not in use on this connection. Waiting for a relation data file to be truncated. Name of this database, or NULL for shared objects. Waiting for other Parallel Hash participants to finish repartitioning. Waiting a new WAL segment created by copying an existing one to reach durable storage. Waiting to read or update background worker state. PostgreSQL also supports reporting dynamic information about exactly what is going on in the system right now, such as the exact command currently being executed by other server processes, and which other connections exist in the system. OID of the database this backend is connected to, Name of the database this backend is connected to. 202302_Serendipity_Shy_CSDN Waiting to read or update the control file or creation of a new WAL file. Waiting to receive bytes from a shared message queue. Number of backends currently connected to this database, or NULL for shared objects. Returns the wait event type name if this backend is currently waiting, otherwise NULL. Logical decoding plugins may optionally emit tracking messages; if they do not, the tracking mechanism will simply display NULL lag. If the state is active and wait_event is non-null, it means that a query is being executed, but is being blocked somewhere in the system. Additional functions related to statistics collection are listed in Table28.19. block. This field is truncated if the DN field is longer than, Number of WAL files that have been successfully archived, Name of the last WAL file successfully archived, Time of the last successful archive operation, Number of failed attempts for archiving WAL files, Name of the WAL file of the last failed archival operation, Time of the last failed archival operation, Time at which these statistics were last reset, Number of scheduled checkpoints that have been performed, Number of requested checkpoints that have been performed, Total amount of time that has been spent in the portion of checkpoint processing where files are written to disk, in milliseconds, Total amount of time that has been spent in the portion of checkpoint processing where files are synchronized to disk, in milliseconds, Number of buffers written during checkpoints, Number of buffers written by the background writer, Number of times the background writer stopped a cleaning scan because it had written too many buffers, Number of buffers written directly by a backend, Number of times a backend had to execute its own. If the argument is NULL, resets statistics for all the replication slots. Waiting to find or allocate space in shared memory. To minimize skew, stats_fetch_consistency can be set to snapshot, at the price of increased memory usage for caching not-needed statistics data. buffer_mapping: Waiting to associate a data block with a buffer in the buffer pool. Waiting for a replication slot to become inactive so it can be dropped. Waiting in main loop of logical replication launcher process. There is no order to the granting of LWLocks and in a high concurrency system this can cause contention. If the argument is NULL, reset statistics for all subscriptions. Waiting to access a parallel query's information about composite types. Postgres Source Code Docs: Locking Overview. Waiting for a write while adding a line to the data directory lock file. Waiting to retrieve messages from the shared catalog invalidation queue. Waiting in a cost-based vacuum delay point. Waiting for any activity when processing replies from WAL receiver in WAL sender process. Waiting to acquire a speculative insertion lock.
New Tarleton Rodeo Facility, Cushman Police Scooter For Sale, Justin Bieber Daughter Photos, Articles L