[Dovecot] FreeBSD 6.1-RELEASE/kqueue high CPU load

[Taras Savchuk]

Here are ktrace chunks and some statistics (process uses ~70% CPU, 
states of process - RUN/kqread, ~30-50% system CPU load):

mail2# head -n 5 47651.ktrace.4.log.txt
  47651 imap     0.000000 RET   lstat 0
  47651 imap     0.001906 CALL  lstat(0x8111d60,0xbfbfe540)
  47651 imap     0.001911 NAMI 
"/var/email/elantech.ru/taras/Maildir/.Lists.dovecot/cur/1165899508.P13178Q191.mail2.elantech.ru:2,b"
  47651 imap     0.001951 RET   lstat 0
  47651 imap     0.002315 CALL  lstat(0x8111d60,0xbfbfe540)
mail2# tail -n 5 47651.ktrace.4.log.txt
  47651 imap     16.514815 CALL  lstat(0x8111ec0,0xbfbfe4e0)
  47651 imap     16.514818 NAMI 
"/var/email/elantech.ru/taras/Maildir/.Lists.dovecot/cur/1166721346.P51379Q78.mail2.elantech.ru:2,b"
  47651 imap     16.514842 RET   lstat 0
  47651 imap     16.514868 CALL  lstat(0x8111ec0,0xbfbfe4e0)
  47651 imap     16.514871 NAMI 
"/var/email/elantech.ru/taras/Maildir/.Lists.dovecot/cur/1166721942.P51379Q83.mail2.elantech.ru:2,b"
mail2# cat 47651.ktrace.4.log.txt | grep lstat | wc -l
   530528
mail2# cat 47651.ktrace.4.log.txt | grep kevent | wc -l
       12
mail2# cat 47651.ktrace.4.log.txt | grep gettimeofday | wc -l
       30
mail2#

500K lstat calls in 17 seconds is not too much?

Timo Sirainen пишет:
> On Sun, 2007-03-11 at 01:48 +0300, Taras Savchuk wrote:
>> I'm installed dovecot_rc26, but still have likely the same problem:
>>
>> 46642 email            1 117    0  3552K  1968K RUN    0   1:15 75.20% imap
> 
> Could you tell me what it's doing?
> http://wiki.dovecot.org/Debugging/ProcessTracing
> 
> Also a gdb backtrace could help:
> 
> gdb attach 46642
> bt full
> 
> And did you try if the problem goes away by not using kqueue?
> 

-- 
С уважением, Савчук Тарас
ООО "Элантек" : Аутсорсинг ИТ, WEB-разработка
http://www.elantech.ru
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