[squid-users] High CPU load with diskd: back to ufs

Ok, I've given up after a week and restarted squid using ufs
today at 13:30 in France.

Now, MRTG graphs are showing a lower CPU usage for our squid proxy,
as cachemgr.cgi (CPU Usage, 60 minute avg: 23.25%) and vmstat:

> vmstat 1 10
Virtual Memory Statistics: (pagesize = 8192)
  procs memory pages intr cpu
  r w u act free wire fault cow zero react pin pout in sy cs us sy id
  2 111 32 48K 1509 12K 359K 74K 145K 278 44K 0 4K 187K 4K 21 40 39
  3 110 32 48K 1492 12K 5 16 18 0 28 0 3K 2K 3K 10 41 49
  3 110 32 48K 1458 12K 0 0 0 0 0 0 5K 4K 4K 19 25 56
  2 110 33 48K 1422 12K 0 0 0 0 0 0 4K 2K 4K 13 44 43
  2 110 33 48K 1403 12K 1 0 0 0 0 0 6K 4K 5K 23 28 48
  3 110 32 48K 1365 12K 0 0 1 0 0 0 5K 3K 4K 13 47 40
  2 111 32 48K 1367 12K 0 0 0 0 0 0 6K 4K 6K 20 30 50
  5 109 31 48K 1340 12K 0 0 0 0 0 0 6K 2K 5K 12 44 44
  2 111 32 48K 1326 12K 0 0 0 0 0 0 4K 3K 5K 13 22 65
  5 109 31 48K 1292 12K 0 0 0 0 0 0 6K 3K 5K 14 39 47

Curiously, top and dxsysinfo (a Dec tool) keep saying CPU load is
very high:
load averages: 1.39, 1.46, 1.38 14:55:52
62 processes: 1 running, 1 waiting, 14 sleeping, 46 idle
CPU states: 23.7% user, 0.0% nice, 65.4% system, 10.7% idle
Memory: Real: 297M/489M act/tot Virtual: 1500M use/tot Free: 9200K

  PID USERNAME PRI NICE SIZE RES STATE TIME CPU COMMAND
 3557 root 42 0 154M 151M WAIT 17:25 20.20% squid
 3578 squid 42 0 1776K 196K sleep 0:20 0.40% unlinkd
 3645 root 44 0 8920K 6086K run 0:00 0.20% top
...

Who's right ?
Any advice ?

My squid is really slow.

> I've upgraded from squid-2.5.STABLE4 to squid-2.5.STABLE5 on a
> Tru64Unix 5.1 alpha XP1000.
>
> First I've started 2.5.ST5 Monday at noon using ufs.
> Then I've restarted 2.5.ST5 Tuesday at noon using diskd.
>
> Just see at:
> http://www.univ-st-etienne.fr/criter/stats/mrtg/cpu.janon.html
>
> CPU load is, say, twice the load of squid before using diskd.
> Also, nightly CPU load is really higher than squid-2.5.ST4
>
> It seems squid is using CPU, not diskd:
> janon/root> ps aux
> USER PID %CPU %MEM VSZ RSS TTY S STARTED TIME COMMAND
> squid 3931 77.2 34.5 181M 176M ?? R Mar 09 10:20:10 (squid)
> root 0 17.3 5.3 643M 27M ?? R < Mar 08 08:55:50 [kernel
> idle]
> squid 3953 1.5 0.1 2.63M 480K ?? U Mar 09 18:45.20 diskd 40
> 25344 4025345 4025346
>
> >From cachemgr.cgi:
> CPU Usage, 5 minute avg: 77.92%
> CPU Usage, 60 minute avg: 76.15%
>
> I thought diskd would help our squid cache under heavy load
> (2,000+ clients, more than 60 requests/second, very long answers)
>
> Any idea ?
> Thanks in advance.

-- 
_________________________________________________________________
Magali BERNARD - CRITeR - Université Jean Monnet de Saint-Etienne
23 rue du Dr Paul Michelon - 42023 St-Etienne Cedex 2 - FRANCE
Tel: 04.77.48.50.62