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diff --git a/doc/src/sgml/ref/pgtestfsync.sgml b/doc/src/sgml/ref/pgtestfsync.sgml new file mode 100644 index 0000000..e811f80 --- /dev/null +++ b/doc/src/sgml/ref/pgtestfsync.sgml @@ -0,0 +1,127 @@ +<!-- +doc/src/sgml/ref/pgtestfsync.sgml +PostgreSQL documentation +--> + +<refentry id="pgtestfsync"> + <indexterm zone="pgtestfsync"> + <primary>pg_test_fsync</primary> + </indexterm> + + <refmeta> + <refentrytitle><application>pg_test_fsync</application></refentrytitle> + <manvolnum>1</manvolnum> + <refmiscinfo>Application</refmiscinfo> + </refmeta> + + <refnamediv> + <refname>pg_test_fsync</refname> + <refpurpose>determine fastest <varname>wal_sync_method</varname> for <productname>PostgreSQL</productname></refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>pg_test_fsync</command> + <arg rep="repeat"><replaceable>option</replaceable></arg> + </cmdsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para> + <application>pg_test_fsync</application> is intended to give you a reasonable + idea of what the fastest <xref linkend="guc-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 + <application>pg_test_fsync</application> might not make any significant + difference in real database throughput, especially since many database servers + are not speed-limited by their write-ahead logs. + <application>pg_test_fsync</application> reports average file sync operation + time in microseconds for each <literal>wal_sync_method</literal>, which can also be used to + inform efforts to optimize the value of <xref linkend="guc-commit-delay"/>. + </para> + </refsect1> + + <refsect1> + <title>Options</title> + + <para> + <application>pg_test_fsync</application> accepts the following + command-line options: + + <variablelist> + + <varlistentry> + <term><option>-f</option></term> + <term><option>--filename</option></term> + <listitem> + <para> + Specifies the file name to write test data in. + This file should be in the same file system that the + <filename>pg_wal</filename> directory is or will be placed in. + (<filename>pg_wal</filename> contains the <acronym>WAL</acronym> files.) + The default is <filename>pg_test_fsync.out</filename> in the current + directory. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-s</option></term> + <term><option>--secs-per-test</option></term> + <listitem> + <para> + 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. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-V</option></term> + <term><option>--version</option></term> + <listitem> + <para> + Print the <application>pg_test_fsync</application> version and exit. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-?</option></term> + <term><option>--help</option></term> + <listitem> + <para> + Show help about <application>pg_test_fsync</application> command line + arguments, and exit. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + + </refsect1> + + <refsect1> + <title>Environment</title> + + <para> + The environment variable <envar>PG_COLOR</envar> specifies whether to use + color in diagnostic messages. Possible values are + <literal>always</literal>, <literal>auto</literal> and + <literal>never</literal>. + </para> + </refsect1> + + <refsect1> + <title>See Also</title> + + <simplelist type="inline"> + <member><xref linkend="app-postgres"/></member> + </simplelist> + </refsect1> +</refentry> |