Dovecot 1.0 rc7 on FreeBSD 6.1-RELEASE/i386 with kqueue eats much CPU

[Taras Savchuk]

I have a problem with dovecot eating sometimes up to 90% CPU.

While making such high cpu load, dovecot calls gettimeofday() more than 
20000 times per second:

mail2# cat k.dov.l.txt | grep CALL | grep gettimeofday | wc -l
1195552
mail2# head -n 1 k.dov.l.txt
20910 imap 0.000000 CALL gettimeofday(0x80c2c60,0x80c2c68)
mail2# tail -n 1 k.dov.l.txt
20910 imap 51.826065 RET gettimeofday 0

Here is my kdump: http://www.elantech.ru/kdump-dovecot.txt.gz
top shows high system load (~50%) and small user load (~0-5%).


We discussed this problem in dovecot@ mailing list ( 
http://www.dovecot.org/list/dovecot/2006-September/016096.html ),
and people from dovecot@ recomended me to send this problem also to 
freebsd-stable@ and freebsd-current at .

Thanks for help in advance!

-- 
С уважением, Савчук Тарас
ООО "Элантек" : Аутсорсинг ИТ, WEB-разработка
http://www.elantech.ru
+7 (495) 589 68 81
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