RE: [squid-users] High loads on linux box running squid - tuning

[root@proxy log]# free
             total used free shared buffers cached
Mem: 1025432 1009236 16196 0 164296 394932
-/+ buffers/cache: 450008 575424
Swap: 2097112 28500 2068612

 3097 squid 25 0 72060 70M 1928 S 62.5 7.0 11:07 0 squid

Kær kveðja / Best regards,
Finnur Ö. Guðmundsson
System Engineer - System Operations
fog@t.is

TM Software - Skyggnir
Holtasmári 1, IS- 201 Kópavogur, Iceland
tel: + 354 545 3000-fax + 354 545 3001
www.t.is

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-----Original Message-----
From: Elsen Marc [mailto:elsen@imec.be]
Sent: 17. febrúar 2005 08:54
To: Finnur Örn Guðmundsson - Skyggnir; squid-users@squid-cache.org
Subject: RE: [squid-users] High loads on linux box running squid - tuning

 
> Hi all,
>
> Im running squid on HP Proliant DL360 (3.06Ghz Xeon / 1Gb ram / 2x 15K
> disks in raid1)
>
> We have around 2000-2500 concurrent clients at daytimes
>
> We recently upgraded the squid box from 866Mhz PIII / 1Gb of ram. It
> had 100% cpu loads all the time and it was...slow :)
>
> After i upgraded the box to the 3Ghz Xeon its still performing pretty
> much the same (Loads from 0.80 to 2.00).
> Now i am running Squid 2.5.STABLE3-6.3E2 (from RHEL 3 Update 4). I am
> by no means a squid expert (go figure:) but here are the parameters i
> have changed from defaults (after googling for awile).
>
> cache_mem 128 MB
> cache_swap_low 80
> cache_swap_high 100
> maximum_object_size 1024 KB
> cache_dir aufs /var/spool/squid 4000 16 256 (i know i do not have alot
> of cacheing space, but this is a temp proxy solution) cache_store_log
> none request_body_max_size 12 MB half_closed_clients off
>
> The system is running 2.4.21-27 in non hyperthreading mode. (1 cpu)
>
> Is there anything i can do to quickly lower the load? How many users
> can one put on a box like this? I have been google-ing alot and have
> seen talk about 2500-5000 on one box, not unlike this one. Is this
> wrong?
>
 
  - Check whether the SQUID process has adequate mem. (not swapping) with :
        
        % free
        % top (check SIZE versus RSS of Squid process).

  - I would also advise to have a go with the default setting of 'cache_mem'
    see how that influences CPU usage.

  - From FAQ : http://www.squid-cache.org/Doc/FAQ/FAQ-11.html#ss11.46
    (Probably does not apply).

  M.
Received on Thu Feb 17 2005 - 02:03:51 MST