02-10-2012
You are having the standard Linux Newbie Memory Freakout. Cache memory counts as free memory.
Linux uses every spare bit of memory to cache all disk accesses, because memory which sits around doing nothing is useless. But cache will be recycled for other uses as needed. It's only sitting around as cache right now because it's not needed. Large amounts of cache are to be expected on an unloaded and idle system.
You want to have at least some cache, anyway. If you use so much memory that there's nothing left for cache, this is a problem -- disk access will become slow. The more cache you have, the more efficient disk access can become.
Do not, repeat, do not reboot your system, plug weird values into /proc/ to "flush the cache", and so forth. Everything is fine.
Last edited by Corona688; 02-10-2012 at 11:45 AM..
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LEARN ABOUT DEBIAN
cacheinfo
CACHEINFO(5) AFS File Reference CACHEINFO(5)
NAME
cacheinfo - Defines configuration parameters for the Cache Manager
DESCRIPTION
The cacheinfo file defines configuration parameters for the Cache Manager, which reads the file as it initializes.
The file contains a single line of ASCII text and must reside in the /etc/openafs directory. Use a text editor to create it during initial
configuration of the client machine; the required format is as follows:
<mount>:<cache>:<size>
where
<mount>
Names the local disk directory at which the Cache Manager mounts the AFS namespace. It must exist before the afsd program runs. The
conventional value is /afs. Using any other value prevents traversal of pathnames that begin with /afs (such as pathnames to files in
foreign cells that do use the conventional name). The -mountdir argument to the afsd command overrides this value.
<cache>
Names the local disk directory to use as a cache. It must exist before the afsd program runs. The standard value is /usr/vice/cache,
but it is acceptable to substitute a directory on a partition with more available space. Although the Cache Manager ignores this field
when configuring a memory cache, a value must always appear in it. The -cachedir argument to the afsd command overrides this value.
<size>
Specifies the cache size as a number of 1-kilobyte blocks. Larger caches generally yield better performance, but a disk cache must not
exceed 90% of the space available on the cache partition (85% for AIX systems), and a memory cache must use no more than 25% of
available machine memory.
The -blocks argument to the afsd command overrides this value. To reset cache size without rebooting on a machine that uses disk
caching, use the fs setcachesize command. To display the current size of a disk or memory cache between reboots, use the fs
getcacheparms command.
EXAMPLES
The following example cacheinfo file mounts the AFS namespace at /afs, establishes a disk cache in the /usr/vice/cache directory, and
defines cache size as 50,000 1-kilobyte blocks.
/afs:/usr/vice/cache:50000
SEE ALSO
afsd(8), fs_getcacheparms(1), fs_setcachesize(1)
COPYRIGHT
IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
This documentation is covered by the IBM Public License Version 1.0. It was converted from HTML to POD by software written by Chas
Williams and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.
OpenAFS 2012-03-26 CACHEINFO(5)