Attachment #45401 for bug #70005

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         system.  Most directories are small, using just a single
         fragment (typically 1&nbsp;K) in the file system and less
         (typically 512&nbsp;bytes) in the buffer cache.
         With this variable turned off (to 0), the buffer
         cache will only cache a fixed number of directories even if
         you have a huge amount of memory. When turned on (to 1), this sysctl
         allows the buffer cache to use the VM Page Cache to cache the
         directories, making all the memory available for caching
         directories.  However,
         the minimum in-core memory used to cache a directory is the
         physical page size (typically 4&nbsp;K) rather than 512&nbsp;
         bytes.  We recommend keeping this option on if you are running
         any services which manipulate large numbers of files.  Such
         services can include web caches, large mail systems, and news
         systems. Keeping on this option will generally not reduce
         performance even with the wasted memory but you should
         experiment to find out.</para>
      </sect3>

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Lines 1566-1583 Link Here

(-)conf.fix Mon Jul 26 18:12:22 2004 (-4 / +4 lines)
1566	system. Most directories are small, using just a single	1566	system. Most directories are small, using just a single
1567	fragment (typically 1 K) in the file system and less	1567	fragment (typically 1 K) in the file system and less
1568	(typically 512 bytes) in the buffer cache.	1568	(typically 512 bytes) in the buffer cache.
1569	However, when operating in the default mode the buffer	1569	With this variable turned off (to 0), the buffer
1570	cache will only cache a fixed number of directories even if	1570	cache will only cache a fixed number of directories even if
1571	you have a huge amount of memory. Turning on this sysctl	1571	you have a huge amount of memory. When turned on (to 1), this sysctl
1572	allows the buffer cache to use the VM Page Cache to cache the	1572	allows the buffer cache to use the VM Page Cache to cache the
1573	directories, making all the memory available for caching	1573	directories, making all the memory available for caching
1574	directories. However,	1574	directories. However,
1575	the minimum in-core memory used to cache a directory is the	1575	the minimum in-core memory used to cache a directory is the
1576	physical page size (typically 4 K) rather than 512	1576	physical page size (typically 4 K) rather than 512
1577	bytes. We recommend turning this option on if you are running	1577	bytes. We recommend keeping this option on if you are running
1578	any services which manipulate large numbers of files. Such	1578	any services which manipulate large numbers of files. Such
1579	services can include web caches, large mail systems, and news	1579	services can include web caches, large mail systems, and news
1580	systems. Turning on this option will generally not reduce	1580	systems. Keeping on this option will generally not reduce
1581	performance even with the wasted memory but you should	1581	performance even with the wasted memory but you should
1582	experiment to find out.</para>	1582	experiment to find out.</para>
1583	</sect3>	1583	</sect3>