mod_proxy/345: Cache Expire not effective for high load site

[Steve Slater <sl...@nuc.berkeley.edu>]

>Number:         345
>Category:       mod_proxy
>Synopsis:       Cache Expire not effective for high load site
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apache (Apache HTTP Project)
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Wed Apr  9 18:20:14 1997
>Originator:     slater@nuc.berkeley.edu
>Organization:
apache
>Release:        1.2b7
>Environment:
OSF/1 v4.0 gcc
>Description:
Maybe not a true but but more of an implementation suggestion. The caching
protocol seems to check the cache size only on the specified interval. If you
have a large cache and many users, this cache can grow very rapidly before
apache even checks its size. Conversely, if you check the size too often and
you have a very large cache (100MB+) then it takes too long to check the
size. This combination makes it difficult to have a large cache for a proxy
for a large corporation.	
>How-To-Repeat:

>Fix:
Perhaps having the cache keep a running total of size and expire more often
without the need to completely search the file system. Seems like CERN did
something like this
>Audit-Trail:
>Unformatted: