[Dovecot] Dovecot write activity (mostly 1.1.x)

[mikkel at euro123.dk]

On Sun, November 4, 2007 2:20 pm, Timo Sirainen wrote:
> Well, if you use only clients that don't really need indexes they could
> just slow things down. You could try disabling indexes to see how it works
> then (:INDEX=MEMORY to mail_location).

I tried that earlier and it did result in less writes.
It would be a nice-to-have option to be able to individually tell deliver,
imapd and popd whether they should update indexes and cache.


> Although v1.1 should be writing less to disk than v1.0, because v1.1
> doesn't anymore update dovecot.index as often. v1.1 versions before beta6
> had some problems updating cache file though. They could have updated it
> more often than necessary, and beta5 didn't really even update it at all.

Okay, then I really need to wait and see if things change (it'll probably
take a few days before the majority of e-mail accounts are re-indexed and
cached).

By the way writes increased noticeably when i upgraded from 1.0 to 1.1.
On the other hand reads decreased a lot as well. I guess the
fail-to-update-cache bug you mentioned could have a lot to do with that.


>> (Possibly this is also the answer to my other post regarding
>> stalled/delayed I/O)
>
> You could truss the hanging process to see what it's doing.
>

It's not an easy task since the delay is sometimes just a few (5-10)
seconds. And when there is a complete stall the client aborts before I can
find the process. But I'll give it a go.

Thanks for your input.