MailScanner slow and not taking all resources available

[Glenn Steen]

On 08/12/06, Ugo Bellavance <ugob at camo-route.com> wrote:
> Hi,
>
> This is MailScanner version 4.54.6
>
> It sometimes happen on some servers (not always the same) that suddenly,
> the INQ grows very fast.  When I look at the server, CPU is used only
> at ~ 50% or less and MailScanner is not using the CPU that much.
>
> - The networks seems to be ok (I can easily download a file at 1 MB/s
> (10mbps link).
> - DNS resolution seems to be quick
> - SA doesn't time out
> - System doesn't swap
> - disk i/o doesn't look saturated
>
> Here is an excerpt of dstat output:
> ----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
> usr sys idl wai hiq siq|_read _writ|_recv _send|__in_ _out_|_int_ _csw_
>   51   9  30   9   1   1|   0  1032k|  41k  246k|   0     0 | 998   857
>   64   6  29   0   1   1|   0   136k|  32k  286k|   0     0 | 808   550
>   53   8  39   0   0   1|   0     0 |  61k  625k|   0     0 |1179   530
>   80  13   8   0   0   1|   0     0 |  30k  319k|   0     0 | 846  1350
>   80   9  10   0   1   1|   0     0 |  41k  311k|   0     0 | 824   485
>   84   6  10   0   0   1|   0  1264k|  29k  281k|   0     0 | 913   510
>   54  13  32   0   1   1|   0     0 |  45k  327k|   0     0 | 950   579
>   74  10  16   0   0   2|   0     0 |  52k  317k|   0     0 | 953   984
>   54  16  30   0   0   1|   0     0 |  64k  323k|   0     0 | 995   676
>   18   6  76   0   0   1|   0     0 | 122k  292k|   0     0 |1152  1053
>   62  13  16   9   1   0|   0    19M|  74k  255k|   0     0 |1356  1154
>   64  13  22   0   1   1|   0     0 |  45k  317k|   0     0 | 917   937
>   68   8  25   0   0   0|   0     0 |  51k  325k|   0     0 | 923   558
>   44  21  34   0   1   2|   0   184k|  47k  299k|   0     0 | 969   647
>   47  20  20  13   0   2|   0    19M|  44k   96k|   0     0 |1002   634
>
> top:
>
>   10:07:18  up 40 days,  1:22,  2 users,  load average: 1.62, 1.20, 1.07
> 95 processes: 94 sleeping, 1 running, 0 zombie, 0 stopped
> CPU states:  cpu    user    nice  system    irq  softirq  iowait    idle
>             total   12.0%    0.0%    6.2%   0.0%     0.4%    0.3%   80.6%
>             cpu00   14.2%    0.0%    5.0%   0.2%     0.6%    0.4%   79.6%
>             cpu01    9.9%    0.0%    7.5%   0.0%     0.3%    0.3%   81.6%
> Mem:  3074084k av, 2809584k used,  264500k free,       0k shrd,  134216k
> buff
>                     2141452k actv,  470156k in_d,   25672k in_c
> Swap: 2008104k av,    7580k used, 2000524k free                 1809200k
> cached
>
>    PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND
> 18116 root      18   0 78476  76M  3264 S     3.6  2.5   0:00   1
> MailScanner
> 15502 root      15   0  390M 390M   784 S     3.3 13.0   1:20   1
> milter-greylist
> 15970 root      25   0 13104  12M  3400 S     2.6  0.4   0:10   1 php
>   7807 root      15   0  390M 390M   784 S     1.0 13.0   0:21   1
> milter-greylist
>   7843 root      16   0  390M 390M   784 S     0.9 13.0   0:28   1
> milter-greylist
> 17886 root      15   0 78240  76M  3264 S     0.5  2.5   0:00   1
> MailScanner
> 22380 root      15   0 76008  74M  3248 S     0.1  2.4   0:25   1
> MailScanner
> 17840 root      15   0  1056 1056   812 R     0.1  0.0   0:00   0 top
>
>
> Anyone seeing this as well?
>
Not really no.
SA might not be timing out, but... Have you looked at the digest
checks? Sometimes DCC and/or Pyzor seem to have abominable response
times... On a fairly busy server (can't really call my setup "busy":-)
that would likely have a huge impact.

-- 
-- Glenn
email: glenn < dot > steen < at > gmail < dot > com
work: glenn < dot > steen < at > ap1 < dot > se