Re: LRU frequency

On Mon, 18 Jul 2005, Lucas Brasilino wrote:

> Hi!
>
> I looking around LRU informations to get into the code.
> I read a doc, I really don't remember where, that
> says LRU replacement policy runs every second.
> Is that correct ? So do heap LFUDA and GDSF ?

It is true. This is the call in store.c:

     /* Reregister a maintain event .. */
     eventAdd("MaintainSwapSpace", storeMaintainSwapSpace, NULL, 1.0, 1);

> If so, why LRU threshold is about days (1 to
> 10 days as said here[1])

First, current Squid versions don't really use the notion of "LRU
threshold" anymore.

> and not minutes or
> hours ? Ok.. should be some overhead... but

The LRU threshold represents how long it takes the
cache to go from empty to full. It should be a long
time (days). If the cache becomes full in only a few minutes
(for example) then the cache is probably not big enough.

> I've experienced some very busy caches that
> quits due a full cache directory... in other
> words.. without efficiently swap out objects...

Actually, it means that Squid cannot delete old objects fast
enough to make room for new ones.

What is the cache size and request rate of these
caches that quit due a full cache directory?

Duane W.
Received on Mon Jul 18 2005 - 22:24:30 MDT