Re: [squid-users] Number of Spindles

2008/12/5 Nyamul Hassan <mnhassan_at_usa.net>:
> Thx for the response Adrian. Earlier I was using only AUFS on each drive,
> and the system choked on IOWait above 200 req/sec. But, after I added COSS
> in the mix, it improved VASTLY.

Well, thats why its there, right? :)

>
> Since you're the COSS expert, I would really love to hear about what you
> think of my configuration options for COSS above. Do you think I can
> improve them?

Not off the top of my head, no.

> As for L1 and L2 numbers in AUFS, can you suggest any benchmark tests which
> I can run and give you feedback?

Again, not off the top of my head. I'd look at trying to gather stats
on various types of memory usage and IO patterns and do some
statistical comparisons. I've been focusing on different areas lately
so I'm not really in the "storage" headspace right now :)

> Also, if anybody else can share their ideas / experience, it would be great!
> I'm a bit puzzled about the following:
>
> 1. Although I've set the cache_replacement_policy as differentl to each
> other (GDSF for COSS and LFUDA for AUFS), as has been suggested by the HP
> whitepaper which is referenced in the config file, the "Current Squid
> Configuratoin" page in CacheMGR shows only LFUDA above all the 8 (eight)
> cache_store entries. Does that mean all of them are LFUDA? Isn't GDSF
> better for smaller objects?

COSS will always be LRU. Its the nature of the storage system itself.
You can't override that.

>
> 2. When I had only one type of storage (AUFS), it was easy to find out the
> average objects per cache_store. However, now that I've 2 types on each of
> the 4 HDDs, I can't seem to find out how many of the total 11,000,000 plus
> objects that are being reported in CacheMGR are actually in the COSS and
> AUFS partitions. Is there a way to find that out?

I thought that the storedir page listed the number of objects in the
cache. Hm, if it doesn't then it shouldn't be that difficult to patch
stuff in to track the number of objects in each storedir.

Adrian
Received on Sat Dec 06 2008 - 13:07:04 MST