Metrics for the Sumo Logic PostgreSQL App
This reference lists all of the metrics collected for the Sumo Logic PostgreSQL App, along with an explanation for each metric gauge.
Metrics
Metric Name |
Brief |
Type |
---|---|---|
pg_blks.heap_hit |
Number of buffer hits |
gauge |
pg_blks.heap_read |
Number of disk blocks read |
gauge |
pg_blks.idx_hit |
Number of index buffer hits |
gauge |
pg_blks.idx_read |
Number of index blocks read |
gauge |
hpg_blks.tidx_hit |
Number of TOAST index buffer hits |
gauge |
pg_blks.tidx_read |
Number of TOAST index blocks read |
gauge |
pg_blks.toast_hit |
Number of TOAST buffer hits |
gauge |
pg_blks.toast_read |
Number of disk blocks read |
gauge |
pg_db_size |
Size of the database on disk, in bytes |
gauge |
pg_n_tup_c.del |
Number of delete operations |
gauge |
pg_n_tup_c.hot_upd |
Number of update operations not requiring index update |
gauge |
pg_n_tup_c.ins |
Number of insert operations |
gauge |
pg_n_tup_c.upd |
Number of update operations |
gauge |
pg_n_tup_g.dead |
Number of dead rows in the database |
gauge |
pg_n_tup_g.live |
Number of live rows in the database |
gauge |
pg_numbackends |
Number of server processes |
gauge |
pg_scan.idx |
Number of index scans |
gauge |
pg_scan.idx_tup_fetch |
Number of rows read from index scans |
gauge |
pg_scan.seq |
Number of sequential scans |
gauge |
pg_scan.seq_tup_read |
Number of rows read from sequential scans |
gauge |
pg_xact.commit |
Number of commits |
gauge |
pg_xact.num_deadlocks |
Number of deadlocks detected by the database |
gauge |
pg_xact.rollback |
Number of rollbacks |
gauge |
pg_db_table_size |
Size of the table on disk, in bytes |
gauge |
pg_replication_lag |
time elapsed in seconds since pg_last_xact_replay_timestamp(). |
gauge |
pg_index_scan_stat |
Number of accesses to specific index |
gauge |
Metric gauges
This section provides an explanation for each of the PostgreSQL metrics gauges listed in the previous table.
Metric Gauge |
Description |
---|---|
pg_blks.heap_hit |
This metric shows how many read operations were served from the buffer in memory, so that a disk read was not necessary. This only includes hits in the PostgreSQL buffer cache, not the operating system’s file system cache. |
pg_blks.heap_read |
This metric shows how many disk blocks have been read. |
pg_blks.idx_hit |
This metric shows many index access operations have been served from the buffer in memory. |
pg_blks.idx_read |
This metric shows how many disk blocks have been read by index access operations. |
pg_blks.tidx_hit |
This metric shows how many read operations were served from the buffer in memory, so that a disk read was not necessary. This only includes hits in the PostgreSQL buffer cache, not the operating system’s file system cache. |
pg_blks.tidx_read |
This metric shows how many disk blocks have been read by index access operations on TOAST tables. |
pg_blks.toast_hit |
This metric shows how many TOAST table reads have been served from buffer in memory. |
pg_blks.toast_read |
This metric shows how many disk blocks have been read on TOAST tables. |
pg_db_size |
This metric shows the size of the database on disk, in bytes. |
pg_n_tup_c.del |
This metric shows how many delete operations have been performed. |
pg_n_tup_c.hot_upd |
This metric shows how many update operations have been performed without requiring an index update |
pg_n_tup_c.ins |
This metric shows how many insert operations are performed. |
pg_n_tup_c.upd |
This metric shows how many update operations are performed. |
pg_n_tup_g.dead |
This metric shows how many dead rows in the database. Rows that are deleted or obsoleted by an update are not physically removed from their table; they remain present as dead rows until a VACUUM is done. |
pg_n_tup_g.live |
This metric shows the number of live rows in the database. |
pg_numbackends |
This metric shows how many server processes this database is using. |
pg_scan.idx |
This metric shows how many index scans have been performed across all the tables. |
pg_scan.idx_tup_fetch |
This metric shows how many rows have been read by index scans across all tables. |
pg_scan.seq |
This metric shows how many sequential scans have been performed across all the tables. This is generally referred to as table scan. It is usually the least optimized approach for randomly accessing data in the database tables. |
pg_scan.seq_tup_read |
This metric shows how many rows are read from sequential scans across all the tables. Sequential scans, sometimes referred to as table scans, are the least optimized approach of accessing the data. |
pg_xact.commit |
This metric shows how many commits have been processed by the database. This usually represents the number of transactions performed by the database. |
pg_xact.num_deadlocks |
This metric shows how many deadlocks have been detected by the database. Deadlocks are caused by two or more competing actions that are unable to finish because each is waiting for the other’s lock or resources. |
pg_xact.rollback |
This metric shows how many rollbacks have happened in the database. This could be caused by transactional failure, errors in statements or data validations. |
pg_db_table_size |
This metric shows the size of table(s) on disk, in bytes. |
pg_replication_lag |
This metric shows time elapsed in seconds since the last transaction replayed during recovery. This is the time at which the commit or abort WAL record for that transaction was generated on the primary. |
pg_index_scan_stat |
This metric shows the number of accesses to specific index by table and database. |