|o||One and a half times the result of dividing the cache size by the chunk size (cachesize/chunksize * 1.5).|
|o||The result of dividing the cache size by 10 MB (10,240).|
If the disk cache directory houses fewer Vn files than necessary, the Cache Manager creates new ones, assigning each a unique integer n that distinguishes it from the other files; the integers start with 1 and increment by one for each Vn file created. The Cache Manager removes files if there are more than necessary. The Cache Manager also adds and removes Vn files in response to the fs setcachesize command, which can be used to alter the cache size between reboots.
Vn files expand and contract to accommodate the size of the AFS directory listing or file they temporarily house. As mentioned, by default each Vn file holds up to 64 KB (65,536 bytes) of a cached AFS element. AFS elements larger than 64 KB are divided among multiple Vn files. If an element is smaller than 64 KB, the Vn file expands only to the required size. A Vn file accommodates only a single element, so if there many small cached elements, it is possible to exhaust the available Vn files without reaching the maximum cache size.
Editing or removing the CacheItems or VolumeItems files or a Vn file can cause a kernel panic. If the contents of Vn files seem out of date, clear the files by using the fs flush or fs flushvolume command. If any of the cache files are accidentally modified or deleted, rebooting the machine usually restores normal performance.
To alter cache size (and thus the number of Vn files) between reboots, use the fs setcachesize command. Alternatively, alter the value of the -blocks, -files or -chunksize arguments to the afsd command invoked in the machines AFS initialization file, and reboot. To refresh the contents of one or more Vn files, use the fs flush or fs flushvolume command.
cacheinfo(5), afsd(8), fs_checkvolumes(1), fs_flush(1), fs_flushvolume(1), fs_setcachesize(1)
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