Re: [squid-users] Can a cache be "too big"?

Isaac Witmer wrote:
> On Wed, Jul 21, 2010 at 4:57 PM, Marcus Kool
> <marcus.kool_at_urlfilterdb.com> wrote:
>> yes.
>> 1) the index is in memory and needs 10-20 MB index in memory for each GB on disk
>
> I was under the impression (from the oriely squid manual) that recent
> versions do not use up extra RAM with bigger caches.
> But maybe I read it wrong?
> Also, I'm a bit confused as there's only one apparent "memory" option
> in the squid configuration.
>
> Could you explain/point me to a tutorial?

http://wiki.squid-cache.org/SquidFaq/SquidMemory

>> 2) the housekeeping of the index costs more CPU cycles for a larger cache
>> 3) the housekeeping of the cached objects on disk costs time and grows when the cache is larger. Can be minimised by having cache_swap_low 92 and cache_swap_high 93.
>>
>> The system has 2 GB memory, assuming that the system is dedicated for Squid
>> you need 400 MB for the OS, leaving 1.6 GB for Squid.
>> A safe value for cache_mem would be 500 MB
>>
>> There are many tuning parameters.
>> The best one is to have more disks.
>>
>> Marcus
>>
>> Marcello Romani wrote:
>>> Ralf Hildebrandt ha scritto:
>>>> * Ralf Hildebrandt <Ralf.Hildebrandt_at_charite.de>:
>>>>
>>>>> maximum_object_size 50 MB
>>>>> cache_dir diskd /squid-cache 45000 16 16
>>>>> request_header_max_size 15 KB
>>>>> request_body_max_size 750 MB
>>>>>
>>>>> The machine is 32 bits, MemTotal: 2060960 kB
>>>> Some stats from before "the purge":
>>>>
>>>> 1.4Mio cached objects
>>>> 42GB Cache size
>>>>
>>> Could it be that cache_mem + memory required to manage 42GB of cache caused the squid process to be swapped ?
>>>
>
>
Received on Wed Jul 28 2010 - 17:31:29 MDT