Re: [squid-users] coss storage scheme.

On a related note,

if Squid is configured to use AUFS and COSS for its cache_dirs, does it
store the "Vary Internal Marker Objects" only in the COSS file or
somewhere else too? For my setup, I notice the marker objects which
provide "vary" meta-data for all the cached pages are stored in COSS.

If there is a COSS cache_dir, Squid attempts to store all the cached
objects less than the max_size for COSS object in the COSS file. As a
result, some of the "Internal Marker Objects" get evicted out (during
COSS recycle) thereby resulting in low cache hit ratio for my setup.

On Wed, 2010-01-06 at 16:58 -0800, Chris Robertson wrote:
> Jeronimo Garcia wrote:
> > Hi all.
> >
> > I've been looking at a bunch of benchmarks about storage schemes for
> > squid and coss looks
> > rather impressive , but , reading squid the definitive guide i got to
> > know that the code might be a bit beta/unstable.
> >
>
> http://wiki.squid-cache.org/Features/CyclicObjectStorageSystem
>
> > Now i didn't really check when this book was written but I've been
> > coming across with it for a bunch of years already so i imagine is not
> > very new.
> >
> > Does some of you have some real experiences with coss?
>
> Squid 2.7STABLE6
>
> My COSS dirs are about 45 GB each on bare partitions (cache_dir coss
> /dev/sdc1 46080 max-size=51200 max-stripe-waste=32768 block-size=4096).
> Each server passes about 100 GB of traffic per day (to my customers,
> ~25% from cache), with a peak requests/second of around 150. No issues
> with stability (currently I have over 50 days of uptime).
>
> > I'm also very
> > interested on squid's start-up time when using coss.
> >
>
> Squid starts up just fine but thrashes the disks hard for about half an
> hour while it reads the COSS dirs to build the index. There is no
> noticeable effect on performance.
>
> > Many Thanks
> > -J
> >
>
> Chris
>
Received on Thu Jan 07 2010 - 01:18:16 MST