Re: [squid-users] squid smp fails -k reconfigure

From: Fernando Lozano <fernando_at_lozano.eti.br>
Date: Mon, 09 Jun 2014 11:38:38 -0300

Hi Alex,

First of all, thanks for the feedback.

>
>> I find very strange that workers 6 and 5 try to get aufs cache stores.
>> They are supposed to be the rock store disker and the coordinator! My
>> squid.conf has:
>>
>> workers 4
>> cache_dir aufs /cache/worker${process_number} 25000 16 256 min-size=31001 max-size=346030080
> AUFS store is not SMP-aware. You should not be using it in SMP
> configurations IMO.
Squid configuration examples and the wiki page about SMP tells to use
${process_number} to setup exclusive aufs caches for each worker.

See, for example,
http://wiki.squid-cache.org/ConfigExamples/SmpCarpCluster

Which was the inspiration for my setup.

If we should not use anything except rock store for SMP this should be
explicit in the docs/wiki/faq.

>
>> Is squid -k reconfigure working well for everyone else with SMP?
> Reconfigure does not work well without SMP. It works even worse with
> SMP. Log file rotation is an example of a problematic area specific to SMP.

That's also news to me. I could not find anything on squid-cache.org
stating reconfigure is problematic and should be avoided.

Just to make sure I understand correctly: I shoud restart squid, instead
of reconfiguring, when changing acls, and cope with the downtime?

>
>> Should I try to "hide" those directives from them?
> In general, no. It is best to let your squid.conf reflect the entire
> Squid instance configuration rather than sprinkle it with SMP
> conditionals. Besides, many options have defaults so hiding them will
> not produce the intended results. Squid will eventually learn to ignore
> irrelevant settings on its own.
>
> However, if hiding some directive works around a significant SMP
> problem, hiding it may be better than waiting for others to fix the
> actual problem.
So I'll try to hide the cache_dir aufs from the processes that doesn't
need them, as the default would be having no disk cache. I'll tell you
if this helped or not.

[]s, Fernando Lozano
Received on Mon Jun 09 2014 - 14:39:06 MDT

This archive was generated by hypermail 2.2.0 : Mon Jun 09 2014 - 12:00:04 MDT