| PG_TEST_FSYNC(1) | PostgreSQL 9.6.12 Documentation | PG_TEST_FSYNC(1) |
NAME¶
pg_test_fsync - determine fastest wal_sync_method for PostgreSQLSYNOPSIS¶
pg_test_fsync [option...]
DESCRIPTION¶
pg_test_fsync is intended to give you a reasonable idea of what the fastest wal_sync_method is on your specific system, as well as supplying diagnostic information in the event of an identified I/O problem. However, differences shown by pg_test_fsync might not make any significant difference in real database throughput, especially since many database servers are not speed-limited by their transaction logs. pg_test_fsync reports average file sync operation time in microseconds for each wal_sync_method, which can also be used to inform efforts to optimize the value of commit_delay.OPTIONS¶
pg_test_fsync accepts the following command-line options:-f
--filename
Specifies the file name to write test data in. This file
should be in the same file system that the pg_xlog directory is or will be
placed in. (pg_xlog contains the WAL files.) The default is pg_test_fsync.out
in the current directory.
-s
--secs-per-test
Specifies the number of seconds for each test. The more
time per test, the greater the test's accuracy, but the longer it takes to
run. The default is 5 seconds, which allows the program to complete in under 2
minutes.
-V
--version
Print the pg_test_fsync version and exit.
-?
--help
Show help about pg_test_fsync command line arguments, and
exit.
SEE ALSO¶
postgres(1)| 2019 | PostgreSQL 9.6.12 |