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diff --git a/static/netbsd/man4/wapbl.4 4.html b/static/netbsd/man4/wapbl.4 4.html deleted file mode 100644 index 27b5956b..00000000 --- a/static/netbsd/man4/wapbl.4 4.html +++ /dev/null @@ -1,146 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">WAPBL(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">WAPBL(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">WAPBL</code> — <span class="Nd">Write - Ahead Physical Block Logging file system journaling</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">options WAPBL</code> - <br/> - <code class="Cd">options WAPBL_DEBUG</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">WAPBL</code> driver provides meta-data - journaling for file systems. In particular, it is used with the fast file - system (FFS) to provide rapid file system consistency checking after a - system outage. It also provides better general-use performance over regular - FFS.</p> -<p class="Pp">WAPBL currently maintains its journal in one of two locations:</p> -<dl class="Bl-tag"> - <dt>- After the file system</dt> - <dd>The journal is placed in the same partition as the file system, but - between the file system and the end of the partition.</dd> - <dt>- Within the file system</dt> - <dd>The journal is allocated as a special contiguous file within the file - system. The journal file is not visible via normal file system - access.</dd> -</dl> -<p class="Pp">A new journal is created automatically when a file system is - mounted via <a class="Xr">mount(8)</a> with the <code class="Fl">-o</code> - <var class="Ar">log</var> option. If no journal size has been specified with - <a class="Xr">tunefs(8)</a>, then the size of the journal will be based on - 1MB of journal per 1GB of file system, to a maximum journal size of - 64MB.</p> -<p class="Pp">If there is adequate space between the end of the file system and - the end of the partition, then unless the journal size has been specified - with <a class="Xr">tunefs(8)</a> then the journal will be created after the - file system. To obtain space between the file system and the end of the - partition the size of the partition can be adjusted using - <a class="Xr">disklabel(8)</a>. Care must be taken not to damage existing - data on existing partitions, but this method will work well if, for example, - a swap partition can be shrunk in order to accommodate the journal after the - file system on a partition before the swap partition.</p> -<p class="Pp">For a new file system,</p> -<div class="Bd Pp Bd-indent Li"> -<pre>newfs -s -64m wd0a</pre> -</div> -<p class="Pp">can be used to leave space for a 64MB journal at the end of - <span class="Pa">/dev/wd0a</span>.</p> -<p class="Pp">To specify the size of the journal within the file system - <a class="Xr">tunefs(8)</a> can be used as follows:</p> -<div class="Bd Pp Bd-indent Li"> -<pre>tunefs -l 64m wd0a</pre> -</div> -<p class="Pp">to indicate that a journal of size 64MB on the file system on - <span class="Pa">/dev/wd0a</span> should be created the next time that file - system is mounted. This must be done before the file system is mounted with - the “-o log” option. For existing file systems and general - use, however, simply using</p> -<div class="Bd Pp Bd-indent Li"> -<pre>mount -o log /dev/wd0a /mnt</pre> -</div> -<p class="Pp">will be sufficient to create an appropriate journal within the - file system. Running</p> -<div class="Bd Pp Bd-indent Li"> -<pre>tunefs -l 0 wd0a</pre> -</div> -<p class="Pp">will schedule the log for removal on the next read-write mount, - and running</p> -<div class="Bd Pp Bd-indent Li"> -<pre>tunefs -l 0 wd0a</pre> -</div> -<p class="Pp">followed by</p> -<div class="Bd Pp Bd-indent Li"> -<pre>mount -o log /dev/wd0a /mnt</pre> -</div> -<p class="Pp">will remove the log and then re-create it with the default size. - This method can also be used to grow or shrink the size of the journal by - first scheduling the log for removal, then mounting read-write, but with - logging disabled (so no new log will be created), then unmounting again, - setting the desired log size and finally re-mounting with logging - enabled.</p> -<p class="Pp">With the journal, <a class="Xr">fsck(8)</a> is no longer required - at system boot. If the system has been shutdown in an unclean fashion then - the journal will be replayed when the file system is mounted. - <a class="Xr">fsck(8)</a> can still be used to force a consistency check of - the file system should that be desired.</p> -<p class="Pp">For kernel developers, the compile time option - <code class="Dv">WAPBL_DEBUG</code> turns on debugging.</p> -</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">config(1)</a>, <a class="Xr">fsck(8)</a>, - <a class="Xr">mount(8)</a>, <a class="Xr">newfs(8)</a>, - <a class="Xr">umount(8)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp"><code class="Nm">WAPBL</code> was originally written by - <span class="An">Darrin B. Jewell</span> while at Wasabi Systems Inc. Wasabi - Systems contributed the code to <span class="Ux">NetBSD</span>, and it was - integrated by <span class="An">Simon Burge</span>, <span class="An">Antti - Kantee</span>, <span class="An">Andy Doran</span>, and <span class="An">Greg - Oster</span>.</p> -<p class="Pp"><code class="Nm">WAPBL</code> first appeared in - <span class="Ux">NetBSD 5.0</span>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="CAVEATS"><a class="permalink" href="#CAVEATS">CAVEATS</a></h1> -<p class="Pp">Older releases of the system, and other systems that support the - <code class="Dv">UFS</code> format should only access - <code class="Nm">WAPBL</code> file systems in read-only mode. Additionally, - the <a class="Xr">fsck(8)</a> command from such systems should not be run - against <code class="Nm">WAPBL</code> file systems. Failure to observe these - guidelines may damage the file system.</p> -<p class="Pp"><code class="Nm">WAPBL</code> requires the super block to be in - the UFS2 format. The super block format can be checked using the - <code class="Fl">-s</code> option with <a class="Xr">dumpfs(8)</a>, and - older FFSv1 file systems will need to be updated to the newer super block - layout with the <code class="Fl">-c</code> option to - <a class="Xr">fsck_ffs(8)</a>.</p> -<p class="Pp"><a class="Xr">fsync(2)</a> causes all outstanding metadata - transactions to be committed to disk, introducing additional latency. This - can have an impact on database software and other software that calls - <a class="Xr">fsync(2)</a> often.</p> -<p class="Pp">In-file system log allocation should be done on a relatively quiet - file system. The error path for log allocation failures could result in a - “dangling inode” issue, requiring an <a class="Xr">fsck(8)</a> - to fix.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">December 3, 2012</td> - <td class="foot-os">NetBSD 10.1</td> - </tr> -</table> |