1PG_TEST_FSYNC(1)         PostgreSQL 12.2 Documentation        PG_TEST_FSYNC(1)
2
3
4

NAME

6       pg_test_fsync - determine fastest wal_sync_method for PostgreSQL
7

SYNOPSIS

9       pg_test_fsync [option...]
10

DESCRIPTION

12       pg_test_fsync is intended to give you a reasonable idea of what the
13       fastest wal_sync_method is on your specific system, as well as
14       supplying diagnostic information in the event of an identified I/O
15       problem. However, differences shown by pg_test_fsync might not make any
16       significant difference in real database throughput, especially since
17       many database servers are not speed-limited by their write-ahead logs.
18       pg_test_fsync reports average file sync operation time in microseconds
19       for each wal_sync_method, which can also be used to inform efforts to
20       optimize the value of commit_delay.
21

OPTIONS

23       pg_test_fsync accepts the following command-line options:
24
25       -f
26       --filename
27           Specifies the file name to write test data in. This file should be
28           in the same file system that the pg_wal directory is or will be
29           placed in. (pg_wal contains the WAL files.) The default is
30           pg_test_fsync.out in the current directory.
31
32       -s
33       --secs-per-test
34           Specifies the number of seconds for each test. The more time per
35           test, the greater the test's accuracy, but the longer it takes to
36           run. The default is 5 seconds, which allows the program to complete
37           in under 2 minutes.
38
39       -V
40       --version
41           Print the pg_test_fsync version and exit.
42
43       -?
44       --help
45           Show help about pg_test_fsync command line arguments, and exit.
46

SEE ALSO

48       postgres(1)
49
50
51
52PostgreSQL 12.2                      2020                     PG_TEST_FSYNC(1)
Impressum