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diff --git a/static/freebsd/man4/tarfs.4 3.html b/static/freebsd/man4/tarfs.4 3.html new file mode 100644 index 00000000..b58665ca --- /dev/null +++ b/static/freebsd/man4/tarfs.4 3.html @@ -0,0 +1,125 @@ +<table class="head"> + <tr> + <td class="head-ltitle">TARFS(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">TARFS(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">tarfs</code> — <span class="Nd">tarball + filesystem</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp">To compile this driver into the kernel, place the following line + in your kernel configuration file:</p> +<div class="Bd Pp Bd-indent"><code class="Cd">options TARFS</code></div> +<p class="Pp">Alternatively, to load the driver as a module at boot time, place + the following line in <a class="Xr">loader.conf(5)</a>:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>tarfs_load="YES"</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">tarfs</code> driver implements a read-only + filesystem backed by a <a class="Xr">tar(5)</a> file. Currently, only POSIX + archives, optionally compressed with <a class="Xr">zstd(1)</a>, are + supported.</p> +<p class="Pp">The preferred I/O size for <code class="Nm">tarfs</code> + filesystems can be adjusted using the + <var class="Va">vfs.tarfs.ioshift</var> sysctl setting and tunable. Setting + it to 0 will reset it to its default value. Note that changes to this + setting only apply to filesystems mounted after the change.</p> +<p class="Pp" id="kern.maxphys">When the backing tar file is compressed with + <a class="Xr">zstd(1)</a>, I/O performance can be improved by ensuring that + compressed data is broken up into multiple frames. This helps minimize + unnecessary decompression work. When using <a class="Xr">bsdtar(1)</a> to + create the tar file, this can be achieved using the + <code class="Cm">zstd:max-frame-size</code> and + <code class="Cm">zstd:frame-per-file</code> options. Sensible frame sizes + are powers of 2 between the system's base page size (see + <a class="Xr">arch(7)</a>) and the value of the + <a class="permalink" href="#kern.maxphys"><b class="Sy">kern.maxphys</b></a> + sysctl. Smaller frames will generally yield a worse compression ratio and + require extra kernel memory to maintain an index, and larger frames will on + average require more CPU time to access data when performing random I/O.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DIAGNOSTICS"><a class="permalink" href="#DIAGNOSTICS">DIAGNOSTICS</a></h1> +<p class="Pp">If enabled by the <code class="Dv">TARFS_DEBUG</code> kernel + option, the <var class="Va">vfs.tarfs.debug</var> sysctl setting can be used + to control debugging output from the <code class="Nm">tarfs</code> driver. + Debugging output for individual sections of the driver can be enabled by + adding together the relevant values from the table below.</p> +<table class="Bl-column"> + <tr> + <td>0x01</td> + <td>Memory allocations</td> + </tr> + <tr> + <td>0x02</td> + <td>Checksum calculations</td> + </tr> + <tr> + <td>0x04</td> + <td>Filesystem operations (vfsops)</td> + </tr> + <tr> + <td>0x08</td> + <td>Path lookups</td> + </tr> + <tr> + <td>0x10</td> + <td>File operations (vnops)</td> + </tr> + <tr> + <td>0x20</td> + <td>General I/O</td> + </tr> + <tr> + <td>0x40</td> + <td>Decompression</td> + </tr> + <tr> + <td>0x80</td> + <td>Decompression index</td> + </tr> + <tr> + <td>0x100</td> + <td>Sparse file mapping</td> + </tr> + <tr> + <td>0x200</td> + <td>Bounce buffer usage</td> + </tr> +</table> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">tar(1)</a>, <a class="Xr">zstd(1)</a>, + <a class="Xr">fstab(5)</a>, <a class="Xr">tar(5)</a>, + <a class="Xr">mount(8)</a>, <a class="Xr">sysctl(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">tarfs</code> driver was developed by + <span class="An">Stephen J. Kiernan</span> + <<a class="Mt" href="mailto:stevek@FreeBSD.org">stevek@FreeBSD.org</a>> + and <span class="An">Dag-Erling Smørgrav</span> + <<a class="Mt" href="mailto:des@FreeBSD.org">des@FreeBSD.org</a>> for + Juniper Networks and Klara Systems. This manual page was written by + <span class="An">Dag-Erling Smørgrav</span> + <<a class="Mt" href="mailto:des@FreeBSD.org">des@FreeBSD.org</a>> for + Juniper Networks and Klara Systems.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">February 14, 2023</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |