pg_test_fsync - determine fastest
is intended to give you a reasonable
idea of what the fastest
is on your
as well as supplying diagnostic information in the event of an identified I/O
problem. However, differences shown by
might not make any significant
difference in real database throughput, especially since many database servers
are not speed-limited by their write-ahead logs.
reports average file sync operation
time in microseconds for each
, which can also be used to
inform efforts to optimize the value of
pg_test_fsync accepts the following command-line options:
Specifies the file name to write test data in. This file should be in the same file system that the
pg_waldirectory is or will be placed in. (
pg_walcontains the WAL files.) The default is
pg_test_fsync.outin the current directory.
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.
Print the pg_test_fsync version and exit.
Show help about pg_test_fsync command line arguments, and exit.