chiark / gitweb /
man: drop references to "cgroup" wher appropriate
[elogind.git] / man / systemd-readahead-replay.service.xml
index 3d7d9f5..806d460 100644 (file)
                 <para><filename>systemd-readahead-collect.service</filename></para>
                 <para><filename>systemd-readahead-done.service</filename></para>
                 <para><filename>systemd-readahead-done.timer</filename></para>
-                <para><filename>/usr/lib/systemd/systemd-readahead</filename></para>
+                <cmdsynopsis>
+                        <command>/usr/lib/systemd/systemd-readahead/systemd-readahead</command>
+                        <arg choice="opt" rep="repeat">OPTIONS</arg>
+                        <arg choice="plain">COMMAND</arg>
+                        <arg choice="opt">DIRECTORY | FILE</arg>
+                </cmdsynopsis>
         </refsynopsisdiv>
 
         <refsect1>
@@ -67,7 +72,7 @@
                 time. <filename>systemd-readahead-replay.service</filename>
                 is a service that replays this access data collected
                 at the subsequent boot. Since disks tend to be
-                magnitudes slower than RAM this is intended to improve
+                magnitudes slower than RAM, this is intended to improve
                 boot speeds by pre-loading early at boot all data on
                 disk that is known to be read for the complete boot
                 process.</para>
@@ -75,9 +80,9 @@
                 <para><filename>systemd-readahead-done.service</filename>
                 is executed a short while after boot completed and signals
                 <filename>systemd-readahead-collect.service</filename>
-                to end data collection. On this signal this service
+                to end data collection. On this signal, this service
                 will then sort the collected disk accesses and store
-                information about them disk in
+                information about them in
                 <filename>/.readahead</filename>.</para>
 
                 <para>Normally, both
                 are activated at boot so that access patterns from the
                 preceding boot are replayed and new data collected
                 for the subsequent boot. However, on read-only media
-                where the collected data cannot be stored it might
+                where the collected data cannot be stored, it might
                 be a good idea to disable
                 <filename>systemd-readahead-collect.service</filename>.</para>
 
                 <para>On rotating media, when replaying disk accesses
-                at early boot
+                at early boot,
                 <filename>systemd-readahead-replay.service</filename>
                 will order read requests by their location on disk. On
                 non-rotating media, they will be ordered by their
                 original access timestamp. If the file system supports
-                it
+                it,
                 <filename>systemd-readahead-collect.service</filename>
                 will also defragment and rearrange files on disk to
                 optimize subsequent boot times.</para>
         </refsect1>
 
         <refsect1>
+                <title>Options</title>
+
+                <para><filename>systemd-readahead</filename> understands
+                the following options:</para>
+
+                <variablelist>
+                        <varlistentry>
+                                <term><option>-h</option></term>
+                                <term><option>--help</option></term>
+
+                                <listitem><para>Prints a short help text
+                                and exits.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--max-files=</option></term>
+
+                                <listitem><para>Maximum number of
+                                files to read ahead. Only valid
+                                for thes <command>collect</command>
+                                command.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--file-size-max=</option></term>
+
+                                <listitem><para>Maximum size of files
+                                in bytes to read ahead. Only valid
+                                for the <command>collect</command>
+                                and <command>replay</command>
+                                commands.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--timeout=</option></term>
+
+                                <listitem><para>Maximum time in microseconds
+                                to spend collecting data. Only valid
+                                for the <command>collect</command>
+                                command.</para></listitem>
+                        </varlistentry>
+                </variablelist>
+
+        </refsect1>
+
+        <refsect1>
+                <title>Commands</title>
+
+                <para>The following commands are understood by
+                <filename>systemd-readahead</filename>:</para> <variablelist>
+                        <varlistentry>
+                                <term><command>collect
+                                [<replaceable>DIRECTORY</replaceable>]</command></term>
+                                <listitem>
+                                        <para>Collect read-ahead data on
+                                        early boot. When terminating, it will
+                                        write out a pack file to the indicated
+                                        directory containing the read-ahead
+                                        data. </para>
+                                </listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><command>replay
+                                [<replaceable>DIRECTORY</replaceable>]</command></term>
+                                <listitem>
+                                        <para>Perform read-ahead on the
+                                        specified directory tree.</para>
+                                </listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><command>analyze
+                                [<replaceable>FILE</replaceable>]</command></term>
+                                <listitem>
+                                        <para>Dumps the content of the
+                                        read-ahead pack file to the
+                                        terminal. For each file, the
+                                        output lists approximately how
+                                        much will be read ahead by
+                                        the <command>replay</command>
+                                        command.</para>
+                                </listitem>
+                        </varlistentry>
+
+                </variablelist>
+        </refsect1>
+
+        <refsect1>
                 <title>See Also</title>
                 <para>
                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>