Re: help keeping things in the disk cache nearly forever

John Ruttenberg wrote:

> I can't quite seem to get this behavior, though. Files seem to be removed
> from the cache before it has gotten close to the size specified squid.log:

Squid has a clean up thread that removes the least recently used objects
that has expired or needs to be revalidated from it's cache.

> I can tell that items are no longer in the cache by looking at access.log and
> seeing a TCP_MISS for objects that earlier had TCP_HITs. I can't understand
> store.log; it says RELEASE in cases where I'm sure the object has just been
> added to the disk cache.

Such releases are most likely releases from memory, not disk. If it says
that the file number (the third field, immediately after
RELEASE/SWAPOUT) is FFFFFFFF then the object was purged from memory and
not stored on disk. This is most frequently seen on 304 replies when
browsers validate their locally cached copy of an object which is not in
Squid's cache.

--
Henrik Nordstrom
Squid hacker