Re: [squid-users] ROCK store and UFS (Squid 3.2.3)

On 27.11.2012 11:44, Horacio H. wrote:
> Hi,
>
> I'm testing Squid 3.2.3 and wanted to use ROCK store combined with
> UFS
> or AUFS. Yes, I know it's not currently supported
> (http://wiki.squid-cache.org/Features/RockStore#limitations), but I
> did some tests anyway (Yes, I forgot).

The limitation is about Rock store itself and SMP shared-memory cache.
Is only relevant to UFS when multiple workers are used - because that
enables shared memory cache by default, (use memory_cache_shared OFF to
disable that with workers.)

>
> Doomed to failure, I added this two lines to Squid's default
> configuration:
>
> cache_dir rock /var/cache1 1000 max-size=16384
> cache_dir ufs /var/cache2 2000 16 256 min-size=16384
>
> When both lines were present, objects bigger than 32KB were not
> cached
> (neither on memory or disk). Of course, when ROCK cache_dir was not
> present objects bigger than 16KB were cached on disk at the UFS store
> as expected.
>
> After a few tries, I inverted the order of the lines and increased
> the
> max-size of the rock store, like this:
>
> cache_dir ufs /var/cache2 2000 16 256 min-size=16384
> cache_dir rock /var/cache1 1000 max-size=1048576
>
> Surprisingly, objects bigger than 32KB (up to max-size) were stored
> on
> disk and they got "TCP_HIT" when retrieved. Unfortunately, if Squid
> process was stoped and restarted then those objects were retrieved
> from source again (i.e. UFS storage was ignored or corrupted).

cache.log should contain a trace about why they disappeared again.

I think storing >32KB objects in rock will corrupt them, but not
completely sure on that.

>
> That's when I guessed rock store was not supposed to work that way,
> so
> I hope this little information helps to advance integration with
> UFS...

Please compare your symptoms to
http://bugs.squid-cache.org/show_bug.cgi?id=3686. If you want to
continue testing please try the patch with your original config attempt
- you should see large objects in the UFS dir and small objects going
into the rock dir.

Amos
Received on Tue Nov 27 2012 - 00:02:58 MST