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diff --git a/static/freebsd/man4/ada.4 3.html b/static/freebsd/man4/ada.4 3.html deleted file mode 100644 index 3ef5f31e..00000000 --- a/static/freebsd/man4/ada.4 3.html +++ /dev/null @@ -1,151 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">ADA(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">ADA(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">ada</code> — <span class="Nd">ATA Direct - Access device driver</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="Cd">device ada</code></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The <code class="Nm">ada</code> driver provides support for direct - access devices, implementing the ATA command protocol, that are attached to - the system through a host adapter supported by the CAM subsystem.</p> -<p class="Pp">The host adapter must also be separately configured into the - system before an ATA direct access device can be configured.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="COMMAND_QUEUING"><a class="permalink" href="#COMMAND_QUEUING">COMMAND - QUEUING</a></h1> -<p class="Pp">Command queuing allows the device to process multiple transactions - concurrently, often re-ordering them to reduce the number and length of - seeks. ATA defines two types of queuing: TCQ (Tagged Command Queuing, PATA - legacy) and NCQ (Native Command Queuing, SATA). The - <code class="Nm">ada</code> device driver takes full advantage of NCQ, when - supported. To ensure that transactions to distant parts of the media, which - may be deferred indefinitely by servicing requests closer to the current - head position, are completed in a timely fashion, an ordered transaction is - sent every 7 seconds during continuous device operation.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="CACHE_EFFECTS"><a class="permalink" href="#CACHE_EFFECTS">CACHE - EFFECTS</a></h1> -<p class="Pp">Many direct access devices are equipped with read and/or write - caches. Parameters affecting the device's cache are reported in device - IDENTIFY data and can be examined and modified via the - <a class="Xr">camcontrol(8)</a> utility.</p> -<p class="Pp">The read cache is used to store data from device-initiated read - ahead operations as well as frequently used data. The read cache is - transparent to the user and can be enabled without any adverse effect. Most - devices with a read cache come from the factory with it enabled.</p> -<p class="Pp">The write cache can greatly decrease the latency of write - operations and allows the device to reorganize writes to increase efficiency - and performance. This performance gain comes at a price. Should the device - lose power while its cache contains uncommitted write operations, these - writes will be lost. The effect of a loss of write transactions on a file - system is non-deterministic and can cause corruption. Most devices age write - transactions to limit the vulnerability to a few transactions recently - reported as complete, but it is nonetheless recommended that systems with - write cache enabled devices reside on an Uninterruptible Power Supply (UPS). - The <code class="Nm">ada</code> device driver ensures that the cache and - media are synchronized upon final close of the device or an unexpected - shutdown (panic) event. This ensures that it is safe to disconnect power - once the operating system has reported that it has halted.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYSCTL_VARIABLES"><a class="permalink" href="#SYSCTL_VARIABLES">SYSCTL - VARIABLES</a></h1> -<p class="Pp">The following variables are available as both - <a class="Xr">sysctl(8)</a> variables and <a class="Xr">loader(8)</a> - tunables:</p> -<dl class="Bl-tag"> - <dt id="kern.cam.ada.retry_count"><var class="Va">kern.cam.ada.retry_count</var></dt> - <dd> - <p class="Pp">This variable determines how many times the - <code class="Nm">ada</code> driver will retry a READ or WRITE command. - This does not affect the number of retries used during probe time or for - the <code class="Nm">ada</code> driver dump routine. This value - currently defaults to 4.</p> - </dd> - <dt id="kern.cam.ada.default_timeout"><var class="Va">kern.cam.ada.default_timeout</var></dt> - <dd> - <p class="Pp">This variable determines how long the - <code class="Nm">ada</code> driver will wait before timing out an - outstanding command. The units for this value are seconds, and the - default is currently 30 seconds.</p> - </dd> - <dt id="kern.cam.ada.spindown_shutdown"><var class="Va">kern.cam.ada.spindown_shutdown</var></dt> - <dd> - <p class="Pp">This variable determines whether to spin-down disks when - shutting down. Set to 1 to enable spin-down, 0 to disable. The default - is currently enabled.</p> - </dd> - <dt id="kern.cam.sort_io_queue"><var class="Va">kern.cam.sort_io_queue</var></dt> - <dd style="width: auto;"> </dd> - <dt id="kern.cam.ada."><var class="Va">kern.cam.ada.</var><var class="Ar">X</var><var class="Va">.sort_io_queue</var></dt> - <dd> - <p class="Pp">These variables determine whether request queue should be - sorted trying to optimize head seeks. Set to 1 to enable sorting, 0 to - disable, -1 to leave it as-is. The default is sorting enabled for HDDs - and disabled SSDs.</p> - </dd> - <dt id="kern.cam.ada.read_ahead"><var class="Va">kern.cam.ada.read_ahead</var></dt> - <dd style="width: auto;"> </dd> - <dt id="kern.cam.ada.~2"><var class="Va">kern.cam.ada.</var><var class="Ar">X</var><var class="Va">.read_ahead</var></dt> - <dd style="width: auto;"> </dd> - <dt id="kern.cam.ada.write_cache"><var class="Va">kern.cam.ada.write_cache</var></dt> - <dd style="width: auto;"> </dd> - <dt id="kern.cam.ada.~3"><var class="Va">kern.cam.ada.</var><var class="Ar">X</var><var class="Va">.write_cache</var></dt> - <dd> - <p class="Pp">These variables determine whether device read-ahead and write - caches should be enabled globally or per-device or disabled. Set to 1 to - enable write cache, 0 to disable, -1 to leave it as-is. Values modified - at runtime take effect only after device reset (using the reset - subcommand of <a class="Xr">camcontrol(8)</a>). Because of that, this - setting should be changed in <span class="Pa">/boot/loader.conf</span> - instead of <span class="Pa">/etc/sysctl.conf</span>. The global default - is currently 1. The per-device default is to leave it as-is (follow - global setting).</p> - </dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h1> -<dl class="Bl-tag Bl-compact"> - <dt><span class="Pa">/dev/ada*</span></dt> - <dd>ATA device nodes</dd> -</dl> -</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">ahci(4)</a>, <a class="Xr">cam(4)</a>, - <a class="Xr">da(4)</a>, <a class="Xr">mvs(4)</a>, <a class="Xr">nda(4)</a>, - <a class="Xr">siis(4)</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">ada</code> driver first appeared in - <span class="Ux">FreeBSD 8.0</span>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> -<p class="Pp"><span class="An">Alexander Motin</span> - <<a class="Mt" href="mailto:mav@FreeBSD.org">mav@FreeBSD.org</a>></p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">December 20, 2017</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |