Updated on 2024-11-05 GMT+08:00

PGXC_STAT_BGWRITER

PGXC_STAT_BGWRITER displays statistics on the background writer of each node in the cluster. All columns except node_name are the same as those in the PG_STAT_BGWRITER view. Only users with system administrator permissions can access this view.

Table 1 PGXC_STAT_BGWRITER columns

Column

Type

Description

node_name

text

Node name

checkpoints_timed

bigint

Number of scheduled checkpoints that have been performed

checkpoints_req

bigint

Number of requested checkpoints that have been performed

checkpoint_write_time

double precision

Total amount of time that has been spent in the portion of checkpoint processing where files are written to disk, in milliseconds

checkpoint_sync_time

double precision

Total amount of time that has been spent in the portion of checkpoint processing where files are synchronized to disk, in milliseconds

buffers_checkpoint

bigint

Number of buffers written during checkpoints

buffers_clean

bigint

Number of buffers written by the background writer

maxwritten_clean

bigint

Number of times the background writer stopped a cleaning scan because it had written too many buffers

buffers_backend

bigint

Number of buffers written directly by a backend

buffers_backend_fsync

bigint

Number of times that a backend has to execute fsync

buffers_alloc

bigint

Number of buffers allocated

stats_reset

timestamp with time zone

Time at which these statistics were reset