Re: [squid-users] time to tune further??

I don't know. ;-)

Seriously, it depends on your needs. As long as performance stays
'snappy' you can just keep raising the size until you're happy with it.
  Look at your current Squid process size, and if it isn't 'too big'
(i.e. causing much of your other processes to be forced into swap and
making the system sluggish overall) then increase the cache size. See
if it remains fast at serving Squid requests, and the system continues
to handle normal command line functions without hesitation. Do these
checks at your peak load, of course.

I've configured a few 512MB machines...and I've set them up with about
22GB of total cache_dir space--cache_mem at 48MB or 64MB. It seems to
work well, with the Squid process sitting at just over 250MB, and plenty
of room for the rest of the system to live and the buffer cache to do
it's job.

But there is no rule. Just rules of thumb.

Good luck!

khiz code wrote:

> oh thanks joe
> and all this whil ei was under the impression that cache_mem also
> includes swap.state which i beleive is the meta index of all the
> cached objects
> so for my 512 MB ram machine how large do you think my cache_dir
> capacity should be .. large enuf and yet small to avoid swapping
> rgds
> khizcode
>
>
> --- Joe Cooper <joe@swelltech.com> wrote:
>
>>No. You've misunderstood me, Khiz.
>>
>>The ratio I mentioned is how much memory Squid /will/ use. Not how
>>much
>>you should configure in cache_mem. cache_mem is completely separate
>>from the a amount needed by Squid to keep up with it's swap.state and
>>
>>other necessary stuff.
>>
>>cache_mem is for in-transit objects, hot objects and a few other odds
>>
>>and ends. You define it to be whatever you want, 2MB or 200MB, and
>>Squid won't care--it will /still/ use about 10MB for each 1GB of
>>cache_dir. cache_mem is used in addition to this memory.
>>
>>In some circumstances it may be appropriate to raise the cache_mem in
>>
>>order to improve performance. I've found that, if you have enough
>>memory to spare, Squid can gain about 5%-10% improvement in overall
>>throughput and response times from having a larger cache_mem setting
>>(up
>>to a certain point, dependent on your workload).
>>
>>But there is no correlation between cache_dir size and cache_mem
>>size,
>>and there doesn't need to be.
>>
>>khiz code wrote:

                                   --
                      Joe Cooper <joe@swelltech.com>
                  Affordable Web Caching Proxy Appliances
                         http://www.swelltech.com
Received on Thu Oct 04 2001 - 05:46:49 MDT