On 12/14/11 2:18 PM, James Chris Beaver wrote:
Is there an algorithm for sizing? Is it possible to have a disk that is too
large? Is it possible to have a too many disks?
Yes, you are limited by RAM. The more disk, the more RAM you will consume.
There's also a configuration here that will help with RAM consumption:
CONFIG proxy.config.cache.min_average_object_size INT 8000
Basically, for every 8KB of disk cache, one directory entry is created. And
each directory entry consumes memory (10 bytes if I recall). So, if you
average object sizes are much larger than e.g. 8KB, it's worthwhile to tune
this setting. Likewise if your average objects are much smaller than 8k.
There's also some overhead when ATS "syncs" this directory to disk (the
larger the directory, the more disk I/O to sync it to disk).
Don't ask me why the default is 8000 and not 8192, John might know :).
-- leif
