Re: [squid-users] cache size and structure

>> cache_dir ufs /usr/local/cache/1 3500 128 256
>> cache_dir ufs /usr/local/cache/2 2500 128 256
>>
>
> I'd strongly suggest using "aufs" instead of "ufs".

if I have 1 Mbps for a week my cache size should be 76 GB, but now I have 6
GB
My cache searching will decrease if my disk cache is so big ?!

>> You can, but why would you want to? The suggestion is one cache_dir per
>> spindle to spread the IO load. Putting multiple partitions on one
>> spindle makes about the same sense as multiple cache_dirs in the same
>> partition. Access to all of them will be contending for the limited IO
>> resources available.
>

What do you want to say with "spindle" word ? What means ?

This is entirely dependent on the filesystem you are using and the
> number of objects you cache. The goal is to keep the number of files per
> directory reasonable, because most filesystems are not optimized for a
> "large" ratio (10s of thousands of files per directory).

I'm using Debian 5 with ext3 fs.

----- Origin

al Message -----
From: "Chris Robertson" <crobertson_at_gci.net>
To: <squid-users_at_squid-cache.org>
Sent: Tuesday, June 23, 2009 11:07 PM
Subject: Re: [squid-users] cache size and structure

> Riccardo Castellani wrote:
>> I'm preparing new squid machine and I'm defining cache size.
>> Old squid had 2 entries into "cache_dir directive" :
>> cache_dir ufs /usr/local/cache/1 3500 128 256
>> cache_dir ufs /usr/local/cache/2 2500 128 256
>>
>
> I'd strongly suggest using "aufs" instead of "ufs".
>
>> My cache traffic volume (I/O) is about 2 Mbps a week with peaks of 3
>> Mbps.
>> This squid cache is the parent of 2 other squid machines and it gives
>> answers to about 1000 users.
>>
>> 1- I read you suggest 1 cache_dir to same partition, why I can't use 2
>> folder in tha same partition ?!
>>
>
> You can, but why would you want to? The suggestion is one cache_dir per
> spindle to spread the IO load. Putting multiple partitions on one spindle
> makes about the same sense as multiple cache_dirs in the same partition.
> Access to all of them will be contending for the limited IO resources
> available.
>
>> 2- What do you think my caches size ? 3500 and 2550 ?
>
> Depends on your memory load. A larger cache leads to storing more
> objects, which requires more memory to track. The suggestion I recall is
> "a week's worth of traffic". If you are seeing an average of 2Mbit/s 24
> hours a day, seven days a week, that would lead to a cache of around
> 150GB.
>
>> and its directory structure (128,256) ?!
>>
>
> This is entirely dependent on the filesystem you are using and the number
> of objects you cache. The goal is to keep the number of files per
> directory reasonable, because most filesystems are not optimized for a
> "large" ratio (10s of thousands of files per directory).
>
> Chris
>
>
Received on Thu Jun 25 2009 - 20:52:02 MDT