[DBMail 0000964]: Imap Deamon stop to work randomly

A NOTE has been added to this issue. 
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http://www.dbmail.org/mantis/view.php?id=964 
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Reported By:                bajizs
Assigned To:                
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Project:                    DBMail
Issue ID:                   964
Category:                   IMAP daemon
Reproducibility:            random
Severity:                   crash
Priority:                   normal
Status:                     new
target:                      
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Date Submitted:             23-Mar-12 12:37 CET
Last Modified:              09-Nov-13 10:09 CET
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Summary:                    Imap Deamon stop to work randomly
Description: 
For last 14 days the dbmail-imapd randomly hangs up and stopped to work. In
error and system logs I have nothing (file_logging_levels= 63). I can't
turn on logging on debug level, because this is a production server with
high mail load. Other applications works normally (dbmail-lmtpd,
dbmail-timsieved, mysql, apache, smb etc). Turned on TLS, and heavy used
function by users. The CPU usage by dbmail-imapd always 80-100% (server is
with 2 cores, CPU usage can be 200%). The dbmail-imapd app two times hangs
up at the times when no user logged in - at the night. In this time we make
backup some files, we have haevy hdd and memory usage. We try to solve
problem with more memory - at the moment I don't know result, because we
order new memory banks today. Can be this solve the problem? Can i see why
is the CPU usege to high? Can I see why hangs up the process at random
time?
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 (0003426) Bobbnz (reporter) - 24-Mar-12 20:54
 http://www.dbmail.org/mantis/view.php?id=964#c3426 
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Would seem to me you do have insufficient RAM for high load. Also, have you
followed the recommended procedures for optimizing mysql? 

http://dbmail.org/dokuwiki/doku.php/mysql_notes

I would also be curious to know what you consider to be high load in terms
of messages/day, and also the type of storage you are using, eg
SCSI/SAS/SATA?

 

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 (0003428) bajizs (reporter) - 03-Apr-12 07:48
 http://www.dbmail.org/mantis/view.php?id=964#c3428 
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I think, the database is optimal - don't see any problem in performance
status informations. 

Storage: SATA raid mirror

CC 800 recived mail for the day, from 08:00AM to 02:00PM CC 550 mail, but
all this mails stored in server (Only IMAP is allowed for users). We have
62 user on system, users have 500Mb - 5Gb mails in his IMAP storage.

I dont know why CPU usage is always on 100% by dbmail-imapd (see attached
picture)

 

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 (0003440) bajizs (reporter) - 18-Apr-12 08:03
 http://www.dbmail.org/mantis/view.php?id=964#c3440 
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Memory added to system, but dbmail-imapd CPU usage is 100%. What can be
wrong? 

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 (0003444) bajizs (reporter) - 04-May-12 09:58
 http://www.dbmail.org/mantis/view.php?id=964#c3444 
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OK, memory soves the problem of random crash. The dbmail-imapd don't stop
working after 18 days of work.

Maybe You can add code for logging out of memory exceptions, this can be
solve a lot of problem.

Other side, CPU usage not solved, it is always on 100%. How can see wat
dbmail-imapd do? 

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 (0003607) bajizs (reporter) - 09-Nov-13 10:09
 http://www.dbmail.org/mantis/view.php?id=964#c3607 
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CPU Usage problem solved with new version 3.1.7. (Seams :) ) 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
23-Mar-12 12:37  bajizs         New Issue                                    
24-Mar-12 20:39  Bobbnz         Note Added: 0003426                          
24-Mar-12 20:48  Bobbnz         Note Edited: 0003426                         
24-Mar-12 20:52  Bobbnz         Note Edited: 0003426                         
24-Mar-12 20:54  Bobbnz         Note Edited: 0003426                         
02-Apr-12 17:45  bajizs         File Added: dbmail-100% CPU usage.png           
        
02-Apr-12 17:45  bajizs         Note Added: 0003428                          
03-Apr-12 07:48  bajizs         Note Edited: 0003428                         
18-Apr-12 08:03  bajizs         Note Added: 0003440                          
04-May-12 09:58  bajizs         Note Added: 0003444                          
09-Nov-13 10:09  bajizs         Note Added: 0003607                          
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