syntax.xml

<!--
  Copyright (C) Igor Sysoev
  Copyright (C) Nginx, Inc.
  -->

<!DOCTYPE article SYSTEM "../../../dtd/article.dtd">

<article name="Configuration file measurement units"
         link="/en/docs/syntax.html"
         lang="en"
         rev="4">

<section id="summary">

<para>
nginx supports several measurement units for specifying
sizes, offsets, and time intervals within configuration files.
</para>

</section>


<section id="size" name="Sizes and offsets">

<para>
Sizes can be specified in bytes, kilobytes, or megabytes
using the following suffixes:

<list type="bullet">

<listitem>
<literal>k</literal> and <literal>K</literal> for kilobytes
</listitem>

<listitem>
<literal>m</literal> and <literal>M</literal> for megabytes
</listitem>

</list>
</para>

<para>
For example,
“<literal>1024</literal>”, “<literal>8k</literal>”, “<literal>1m</literal>”.
</para>

<para>
Offsets can be also specified in gigabytes using the
<literal>g</literal> or <literal>G</literal> suffixes.
</para>

</section>


<section id="time" name="Time intervals">

<para>
Time intervals can be specified in milliseconds, seconds,
minutes, hours, days and so on, using the following suffixes:
<table width="30%">
<tr><td width="20%">ms</td><td>milliseconds</td></tr>
<tr><td width="20%">s</td><td>seconds (default)</td></tr>
<tr><td width="20%">m</td><td>minutes</td></tr>
<tr><td width="20%">h</td><td>hours</td></tr>
<tr><td width="20%">d</td><td>days</td></tr>
<tr><td width="20%">w</td><td>weeks</td></tr>
<tr><td width="20%">M</td><td>months, 30 days</td></tr>
<tr><td width="20%">y</td><td>years, 365 days</td></tr>
</table>
</para>

<para>
Multiple units can be combined in a single value
by specifying them in the order from the most to the least significant,
and optionally separated by whitespace.
For example, “<literal>1h 30m</literal>” specifies the same time
as “<literal>90m</literal>” or “<literal>5400s</literal>”.
</para>

<para>
<list type="bullet">

<listitem>
<para>
A value without a suffix means seconds.
</para>
</listitem>

<listitem>
<para>
It is recommended to always specify a suffix.
</para>
</listitem>

<listitem>
<para>
Certain time intervals can be specified only with a seconds resolution.
</para>
</listitem>

</list>
</para>

</section>

</article>