Re: cache_dir size weirdness

On Wed, 29 Sep 1999, Duane Wessels wrote:

>
>
> On Wed, 29 Sep 1999, Chris Dillon wrote:
>
> >
> > I'm running 2.2-STABLE4 (previously STABLE3) on FreeBSD 3.3-STABLE and
> > I just noticed something odd about my cache. From the beginning, I've
> > had my cache directories set up like so:
> >
> > cache_dir /cache.0 6000 16 256
> > cache_dir /cache.1 6000 16 256
> > cache_dir /cache.2 6000 16 256
> >
> > But I've noticed that each cache_dir never seems to grow past about
> > 1.2GB of usage.
> >
> > Filesystem 1K-blocks Used Avail Capacity Mounted on
> > /dev/da0s1g 6625221 1251550 5307419 19% /cache.0
> > /dev/da1s1g 6625221 1252212 5306757 19% /cache.1
> > /dev/da2s1g 6625221 1252062 5306907 19% /cache.2
> >
> > All this time, the following line in the logs has been escaping my
> > eye:
> > Sep 29 10:01:56 cheetah squid[40163]: store_swap_size = 3697752k
> >
> > Does this log entry specify how much data is currently in the cache,
> > or the maximum cache size?
> >
> > I don't think anything else in my config could affect the cache
> > directories and how much they can hold, except possibly a larger
> > maximum_object_size of 8192K.
> >
> > Any ideas?
>
> There is another factor. Check the config parameter called
> 'reference_age'. Objects older than this value are removed.
>
> You might check that value, then look for LRU in cachemgr "info":
>
> squid/src 221> ./client mgr:info|grep LRU
> Storage LRU Expiration Age: 3.78 days
>
> If the two values are the same, then Squid is removing objects even
> though your cache capacity hasn't been reached.

# client mgr:info | grep LRU
        Storage LRU Expiration Age: 365.00 days

I have not changed the reference_age value in the config, which seems
to have a default of 1 month. There is approximately 1GB of incoming
HTTP/FTP traffic per week, so that adds up just about right if it is
discarding items beyond 1 month. I'm guessing there is no harm in
increasing reference_age to 2 months or more.

Thanks for the enlightenment!

-- Chris Dillon - cdillon@wolves.k12.mo.us - cdillon@inter-linc.net
   FreeBSD: The fastest and most stable server OS on the planet.
   For Intel x86 and Alpha architectures (SPARC under development).
   ( http://www.freebsd.org )

   "One should admire Windows users. It takes a great deal of
    courage to trust Windows with your data."
Received on Wed Sep 29 1999 - 15:25:12 MDT