[squid-users] RE: [SPAM?] Re: [squid-users] Optimal maximum cache size

Which leads me onto two more questions:

1. How can I pull up information about the cache, such as the age of
objects within it.

2. When allocating memory to squid, what sort of allowance should be
given to leaving some free for OS file caching since I assume this is
important on some level due to the disk caching...?

Paul Cocker

-----Original Message-----
From: Colin Campbell [mailto:sgcccdc@citec.qld.gov.au]
Sent: 07 November 2007 01:06
To: Matus UHLAR - fantomas
Cc: squid-users@squid-cache.org
Subject: [SPAM?] Re: [squid-users] Optimal maximum cache size
Importance: Low

Hi,

On Tue, 2007-11-06 at 17:33 +0100, Matus UHLAR - fantomas wrote:
> On 05.11.07 19:00, Paul Cocker wrote:
> > Is there such a thing as too much disk cache?

I recall seeing something on the squid-cache web site that said about 1
week is the optimal age for content. How you size the cache is a bit of
a guess. I have two identical systems with 36 GBytes of cache each. One
is doing about 3 times as much traffic as the other (so much for manual
load balancing :-). The busy one has an LRU of 6 days while the quiet
one has dropped down to about 9 days (I'm sure it was about 20 days not
that long ago). That tells me they're not too bad size-wise. Both
systems have just over 2,000,000 store entries. The cache_dir parameters
of interest are: aufs, 19150, 46, 256.

The whole theory behind squid is that it's quicker to get the object
from disk than to retrieve it over the net. Getting objects from memory
is nice but I wouldn't over-emphasise its importance.

Colin

--
Colin Campbell
Unix Support/Postmaster/Hostmaster
Citec
+61 7 3227 6334
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