-
- <varlistentry>
- <term>
- <mallctl>swap.avail</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-stats --enable-swap</option>]
- </term>
- <listitem><para>Number of swap file bytes that are currently not
- associated with any chunk (i.e. mapped, but otherwise completely
- unmanaged).</para></listitem>
- </varlistentry>
-
- <varlistentry id="swap.prezeroed">
- <term>
- <mallctl>swap.prezeroed</mallctl>
- (<type>bool</type>)
- <literal>rw</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>If true, the allocator assumes that the swap file(s)
- contain nothing but nil bytes. If this assumption is violated,
- allocator behavior is undefined. This value becomes read-only after
- <link linkend="swap.fds"><mallctl>swap.fds</mallctl></link> is
- successfully written to.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term>
- <mallctl>swap.nfds</mallctl>
- (<type>size_t</type>)
- <literal>r-</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>Number of file descriptors in use for swap.
- </para></listitem>
- </varlistentry>
-
- <varlistentry id="swap.fds">
- <term>
- <mallctl>swap.fds</mallctl>
- (<type>int *</type>)
- <literal>r-</literal>
- [<option>--enable-swap</option>]
- </term>
- <listitem><para>When written to, the files associated with the
- specified file descriptors are contiguously mapped via
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry>. The resulting virtual memory
- region is preferred over anonymous
- <citerefentry><refentrytitle>mmap</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> and
- <citerefentry><refentrytitle>sbrk</refentrytitle>
- <manvolnum>2</manvolnum></citerefentry> memory. Note that if a file's
- size is not a multiple of the page size, it is automatically truncated
- to the nearest page size multiple. See the
- <link linkend="swap.prezeroed"><mallctl>swap.prezeroed</mallctl></link>
- mallctl for specifying that the files are pre-zeroed.</para></listitem>
- </varlistentry>