1 files changed, 100 insertions, 0 deletions
diff --git a/doc/src/sgml/man1/pg_test_fsync.1 b/doc/src/sgml/man1/pg_test_fsync.1
new file mode 100644
index 0000000..aa14979
--- /dev/null
+++ b/doc/src/sgml/man1/pg_test_fsync.1
@@ -0,0 +1,100 @@
+'\" t
+.\"     Title: pg_test_fsync
+.\"    Author: The PostgreSQL Global Development Group
+.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
+.\"      Date: 2023
+.\"    Manual: PostgreSQL 15.5 Documentation
+.\"    Source: PostgreSQL 15.5
+.\"  Language: English
+.\"
+.TH "PG_TEST_FSYNC" "1" "2023" "PostgreSQL 15.5" "PostgreSQL 15.5 Documentation"
+.\" -----------------------------------------------------------------
+.\" * Define some portability stuff
+.\" -----------------------------------------------------------------
+.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.\" http://bugs.debian.org/507673
+.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
+.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.\" -----------------------------------------------------------------
+.\" * set default formatting
+.\" -----------------------------------------------------------------
+.\" disable hyphenation
+.nh
+.\" disable justification (adjust text to left margin only)
+.ad l
+.\" -----------------------------------------------------------------
+.\" * MAIN CONTENT STARTS HERE *
+.\" -----------------------------------------------------------------
+.SH "NAME"
+pg_test_fsync \- determine fastest \fIwal_sync_method\fR for PostgreSQL
+.SH "SYNOPSIS"
+.HP \w'\fBpg_test_fsync\fR\ 'u
+\fBpg_test_fsync\fR [\fIoption\fR...]
+.SH "DESCRIPTION"
+.PP
+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 write\-ahead 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\&.
+.SH "OPTIONS"
+.PP
+pg_test_fsync
+accepts the following command\-line options:
+.PP
+\fB\-f\fR
+.br
+\fB\-\-filename\fR
+.RS 4
+Specifies the file name to write test data in\&. This file should be in the same file system that the
+pg_wal
+directory is or will be placed in\&. (pg_wal
+contains the
+WAL
+files\&.) The default is
+pg_test_fsync\&.out
+in the current directory\&.
+.RE
+.PP
+\fB\-s\fR
+.br
+\fB\-\-secs\-per\-test\fR
+.RS 4
+Specifies the number of seconds for each test\&. The more time per test, the greater the test\*(Aqs accuracy, but the longer it takes to run\&. The default is 5 seconds, which allows the program to complete in under 2 minutes\&.
+.RE
+.PP
+\fB\-V\fR
+.br
+\fB\-\-version\fR
+.RS 4
+Print the
+pg_test_fsync
+version and exit\&.
+.RE
+.PP
+\fB\-?\fR
+.br
+\fB\-\-help\fR
+.RS 4
+Show help about
+pg_test_fsync
+command line arguments, and exit\&.
+.RE
+.SH "ENVIRONMENT"
+.PP
+The environment variable
+\fBPG_COLOR\fR
+specifies whether to use color in diagnostic messages\&. Possible values are
+always,
+auto
+and
+never\&.
+.SH "SEE ALSO"
+\fBpostgres\fR(1)