[Dovecot] Config review (2.0.5)

[Ralf Hildebrandt]

* Timo Sirainen <tss at iki.fi>:
> On Tue, 2010-10-26 at 11:44 +0200, Ralf Hildebrandt wrote:
> > I traced around a bit today, in dovecot-lda. 
> > A pattern I'm seeing quite often is this:
> > 
> >      0.000853 open("/usr/dovecot-2/lib/dovecot/settings", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 7
> >      0.000463 fcntl64(7, F_GETFD)       = 0x1 (flags FD_CLOEXEC)
> >      0.000555 getdents64(7, /* 8 entries */, 32768) = 360
> >      0.023219 getdents64(7, /* 0 entries */, 32768) = 0
> >      0.001545 close(7)                  = 0
> > 
> > two consecutive getdents64 calls on the same FD, one fast, one slow.
> > WTF?
> 
> I don't know.. Is that directory on local filesystem?

Yes.

> Are your mails on the same disk?

No!

We have:
/dev/sda1 on / type ext3 (rw,errors=panic)
/dev/mapper/volg1-logv1 on /home type ext4 (rw,noexec,nodev,noatime,errors=panic,data=writeback)

> time(NULL) should always be a really fast operation. On my somewhat old
> machine it takes 0.000016 seconds. So if it's taking this long, it seems
> that the system in general is under heavy load and the individual system
> call times don't really tell anything.

Yes, but where does the heavy load come from :)

-- 
Ralf Hildebrandt
  Geschäftsbereich IT | Abteilung Netzwerk
  Charité - Universitätsmedizin Berlin
  Campus Benjamin Franklin
  Hindenburgdamm 30 | D-12203 Berlin
  Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
  ralf.hildebrandt at charite.de | http://www.charite.de