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 >
