Re: [squid-users] High load server Disk problem

On Mon, 23 Aug 2010 13:11:49 -0300, Robert Pipca <robertpipca_at_gmail.com>
wrote:
> Hi,
>
> 2010/8/19 Amos Jeffries <squid3_at_treenet.co.nz>:
>> Your COSS dirs are already sized at nearly 64GB each (65520 MB). With
>> objects up to 1MB stored there. That holds most Windows updates, which
>> are
>> usually only a few hundred KB each.
>> I'm not sure what your slice size is, but 15 of them are stored in RAM
at
>> any given time. You may want to increase that membuf= parameter a bit,
or
>> reduce the individual COSS dir size (requires a COSS dir erase and
>> rebuild).
>
> I'm trying to increase the membuf= parameter on COSS, but I had to
> reduce the cache_dir (from 65520) size in order to do it:
>
> cache_dir coss /cache/coss1 60520 max-size=1048575
> max-stripe-waste=32768 block-size=4096 membufs=100
> cache_dir coss /cache/coss2 60520 max-size=1048575
> max-stripe-waste=32768 block-size=4096 membufs=100
> cache_dir coss /cache/coss3 60520 max-size=1048575
> max-stripe-waste=32768 block-size=4096 membufs=100
>
> Do you guys have any idea if changing from 15 to 100 is enough? Is
> there a way I can test this?
>
> As far as the slice size goes, I don't know either :)
>
> I compiled squid with default COSS options, so I guess it's the 1MB
> default stripe size. Is this it?
>
> One last thing: Where there's a documentation commenting on the
> real-life benefits on using --enable-coss-aio-ops? Is there any?

I'm not aware of anything particular on that option. It allows COSS to use
AIO threads for parallel slice read/write to the background disk so common
sense indicates it should be faster than a single-threaded queue.

>
> I could help running some tests and create some documentation for the
> COSS wiki page, if you think it'll help other people...I just need
> help with some pointers on how to go about testing it right.
>

Ref: http://wiki.squid-cache.org/Features/CyclicObjectStorageSystem

Wonderful. Please do. If you do not already have a wiki account with
editing set let me know (privately) what your login name is and I'll set it
to editor.

Amos
Received on Tue Aug 24 2010 - 03:00:32 MDT