Re: [squid-users] Squid CPU 100% infinite loop

Hi Alex,
thanks for your reply. I have tried to analyse my logs, but... nothing
and this is also disapointed because nothing special is in the logs, and
when we look at them, all seems normal.

Can the FD system limit cause this problem ? I have a system FD limit
of 2048 and squid limit of 1024. This evening squid said, out of
descriptors when it runs in the pseudo "infinite loop" (before nothing
was written with this entry in the logs when the event happened), then i
have increased squid FD limit to 2048. At this moment, I have also
checked FD sockets with netstat -anfinet|grep 3128 and i saw 1700
connections to squid (and maybe nearly 1700 from squid himself). Then
the FD limit was satured. To those FD, we must add FD for squidguard and
DNS requests ? and also FD for logs ? Then theorical 5xFDx1700 =
totalFD ?
Then consequently, squid runs with maxdesc and many connections are
waiting and squid charge increase, am i right ?

This evening i have increased system limits for squid to 16386 and squid
FD limit to 8192, if i'm right, tomorrow no problem will occur.
Can you confirm to me what comportement can squid have when FD limit is
reached ? (CPU charge ?)

Thanks for advance.

-- 
Best regards,
Loïc BLOT, 
UNIX systems, security and network expert
http://www.unix-experience.fr
Le jeudi 16 mai 2013 à 14:55 -0600, Alex Rousskov a écrit :
> On 05/16/2013 07:08 AM, loic.blot wrote:
> 
> > after tests and debug level increased to 5, i am sorry to say: nothing
> > found...
> 
> When I suggested that you collect logs, I did not expect _you_ to
> analyze them. If they are not empty, others may be able to find what is
> wrong with your Squid (if anything). If you post logs, please indicate
> when the "infinite loop" started.
> 
> BTW, does the "infinite loop" condition end on its own if you leave
> Squid running? Or do you have to kill Squid to make it work again?
> 
> And no, Squid core is not multithreaded. There is a storage module that
> uses threads, but you are not using it. Squid also has SMP workers which
> are separate processes, but you are not using them either.
> 
> 
> HTH,
> 
> Alex.
>