[Dovecot] Too many open files, etc.
Hello, a few days ago I switched out UW-server installation to dovecot 0.99.14 (Solaris 9). There were a few client issues, but mostly the migration was ok.
But I have still some questions/problems:
+) dovecot-auth: ... PAM: pipe() failed: Too many open files I increased the max. number of open files. Is this normal behaviour, that more than 512 open files are needed ?
+) we're using mbox on NFS and index files on local disks. When building the index files for the first time, it takes (of course) a long time for large folders. But we have these users, and this will happen sometimes. Is there a way to improve performance ?
+) in general dovecot saves a lot of NFS-bandwidth compared to UW-imap. Thats what I was looking for. But there also seems to be a problem with large inboxes (> 10 MB) and/or large attachments. Is this right ?
One user currently gets this error from Pine when accessing a large attachment: MAIL FOLDER "INBOX" CLOSED DUE TO ACCESS ERROR. AFAIK this error is related to some timeout problem. Has anyone seen this (and a solution for it) ?
Thanks. Martin
Martin Preen, Universitaet Freiburg, Institut fuer Informatik Georges-Koehler-Allee, Geb.52, Zi.00-006, 79110 Freiburg, Germany
phone: ++49 761 203-8250 preen@informatik.uni-freiburg.de fax: ++49 761 203-8242 www.informatik.uni-freiburg.de
Martin Preen wrote:
Hello, a few days ago I switched out UW-server installation to dovecot 0.99.14 (Solaris 9). There were a few client issues, but mostly the migration was ok.
You know, if I had a dollar for every time I'd heard that :) Lots of people seem to be leaving UW-server for Dovecot.
I, too, am running 0.99.14 on Solaris 9 (SPARC)... and loving it :)
But I have still some questions/problems:
+) dovecot-auth: ... PAM: pipe() failed: Too many open files I increased the max. number of open files. Is this normal behaviour, that more than 512 open files are needed ?
I've never seen this problem, but I am not using PAM. Even so, no, it doesn't sound normal. Are there any messages in the logs? How many auth tasks are you running?
+) we're using mbox on NFS and index files on local disks. When building the index files for the first time, it takes (of course) a long time for large folders. But we have these users, and this will happen sometimes. Is there a way to improve performance ?
And still I ask myself "Why do people keep using mbox?" :)
Timo has spoken of a specialised Dovecot LDA for the full 1.0 release. One of the features will be for it to update the indexes upon delivery.
The only other option I can think of is to hack up a quick Python script to connect to an account, and select each of its folders. Hmm... perhaps I will.
One user currently gets this error from Pine when accessing a large attachment: MAIL FOLDER "INBOX" CLOSED DUE TO ACCESS ERROR. AFAIK this error is related to some timeout problem. Has anyone seen this (and a solution for it) ?
Is there anything in the Dovecot logs?
-- Curtis Maloney
On Mon, 2005-02-28 at 11:39 +0100, Martin Preen wrote:
Hello, a few days ago I switched out UW-server installation to dovecot 0.99.14 (Solaris 9). There were a few client issues, but mostly the migration was ok.
But I have still some questions/problems:
+) dovecot-auth: ... PAM: pipe() failed: Too many open files I increased the max. number of open files. Is this normal behaviour, that more than 512 open files are needed ?
Depends on how many logins/sec you have. It's normal if you have >400/s, but probably not otherwise..
+) we're using mbox on NFS and index files on local disks. When building the index files for the first time, it takes (of course) a long time for large folders. But we have these users, and this will happen sometimes. Is there a way to improve performance ?
1.0-tests / dovecot-stable releases take somewhat less time to do it.
+) in general dovecot saves a lot of NFS-bandwidth compared to UW-imap. Thats what I was looking for. But there also seems to be a problem with large inboxes (> 10 MB) and/or large attachments. Is this right ?
One user currently gets this error from Pine when accessing a large attachment: MAIL FOLDER "INBOX" CLOSED DUE TO ACCESS ERROR. AFAIK this error is related to some timeout problem. Has anyone seen this (and a solution for it) ?
Hmm. No idea really.. But I'd rather not spend time trying to figure out 0.99.x bugs. If this is reproduceable with 1.0-tests / dovecot-stable I'll look at it.
Timo Sirainen wrote:
On Mon, 2005-02-28 at 11:39 +0100, Martin Preen wrote:
+) in general dovecot saves a lot of NFS-bandwidth compared to UW-imap. Thats what I was looking for. But there also seems to be a problem with large inboxes (> 10 MB) and/or large attachments. Is this right ?
One user currently gets this error from Pine when accessing a large attachment: MAIL FOLDER "INBOX" CLOSED DUE TO ACCESS ERROR. AFAIK this error is related to some timeout problem. Has anyone seen this (and a solution for it) ?
Hmm. No idea really.. But I'd rather not spend time trying to figure out 0.99.x bugs. If this is reproduceable with 1.0-tests / dovecot-stable I'll look at it.
I've seen this in 1.0-test, but I've only seen it when Pine is accessing a mailbox, then an IMAP session with Dovecot as the server is opened. So...I guess the answer is simple, don't access the mbox via imap while using Pine. ;-)
Frank
"F. Even" wrote:
Timo Sirainen wrote:
On Mon, 2005-02-28 at 11:39 +0100, Martin Preen wrote:
+) in general dovecot saves a lot of NFS-bandwidth compared to UW-imap. Thats what I was looking for. But there also seems to be a problem with large inboxes (> 10 MB) and/or large attachments. Is this right ?
One user currently gets this error from Pine when accessing a large attachment: MAIL FOLDER "INBOX" CLOSED DUE TO ACCESS ERROR. AFAIK this error is related to some timeout problem. Has anyone seen this (and a solution for it) ?
Hmm. No idea really.. But I'd rather not spend time trying to figure out 0.99.x bugs. If this is reproduceable with 1.0-tests / dovecot-stable I'll look at it.
I've seen this in 1.0-test, but I've only seen it when Pine is accessing a mailbox, then an IMAP session with Dovecot as the server is opened. So...I guess the answer is simple, don't access the mbox via imap while using Pine. ;-)
This one seems to be solved. After several tests the user said, that it was just a broken (and large) attachment.
Thanks. Martin
Martin Preen, Universitaet Freiburg, Institut fuer Informatik Georges-Koehler-Allee, Geb.52, Zi.00-006, 79110 Freiburg, Germany
phone: ++49 761 203-8250 preen@informatik.uni-freiburg.de fax: ++49 761 203-8242 www.informatik.uni-freiburg.de
Timo Sirainen wrote:
On Mon, 2005-02-28 at 11:39 +0100, Martin Preen wrote:
Hello, a few days ago I switched out UW-server installation to dovecot 0.99.14 (Solaris 9). There were a few client issues, but mostly the migration was ok.
But I have still some questions/problems:
+) dovecot-auth: ... PAM: pipe() failed: Too many open files I increased the max. number of open files. Is this normal behaviour, that more than 512 open files are needed ?
Depends on how many logins/sec you have. It's normal if you have >400/s, but probably not otherwise..
It's less than 400 login/s. I found that there were an increasing number of login processes (about 500 extra processes per day). In the web archive there is a similar posting (but no answer): http://dovecot.org/list/dovecot/2005-February/006238.html
I tried to fix it using the login parameters. Currently we use login_process_per_connection=no which gives much less extra processes (approx. 100 per day).
Martin
Martin Preen, Universitaet Freiburg, Institut fuer Informatik Georges-Koehler-Allee, Geb.52, Zi.00-006, 79110 Freiburg, Germany
phone: ++49 761 203-8250 preen@informatik.uni-freiburg.de fax: ++49 761 203-8242 www.informatik.uni-freiburg.de
participants (4)
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Curtis Maloney
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F. Even
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Martin Preen
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Timo Sirainen