[asterisk-bugs] [DAHDI-linux 0017620]: High CPU utlization by ksoftirqd since enabling of internal timing in r8053

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17620 
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Reported By:                seanbright
Assigned To:                
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Project:                    DAHDI-linux
Issue ID:                   17620
Category:                   dahdi (the module)
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
JIRA:                        
Reviewboard Link:            
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Date Submitted:             2010-07-10 13:22 CDT
Last Modified:              2010-07-10 22:42 CDT
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Summary:                    High CPU utlization by ksoftirqd since enabling of
internal timing in r8053
Description: 
Running on a Dell PowerEdge R610 with 2 TCE400B transcoder cards.  Also
reproducible on a Dell PowerEdge T310 with no DAHDI hardware at all.

'top' shows ksoftirqd taking up 30-60% of CPU once dahdi is loaded and
load average rises, even without asterisk loaded.  Before r8053, this
problem does not manifest.

I have marked this bug as affecting 2.3.0, but I have tested with
dahdi-linux/trunk and it is still occurring.

Please let me know what other information I can provide.
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 (0124463) sruffell (administrator) - 2010-07-10 22:42
 https://issues.asterisk.org/view.php?id=17620#c124463 
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seanbright:  What kernel / distribution are you running?  Also, are you
running ntpd on this system?  The rate at which interrupts are 'generated'
depends on wall time with the core timer.  So, if the time is actively
being adjusted after loading DAHDI, it is possible for the load to go up
since 'process_masterspan' is being called more frequently than it should
in that case.

If you think time adjustment is possibly related on your system, could you
make sure ntpdate is run before ntp, and both are started before DAHDI? 

Issue History 
Date Modified    Username       Field                    Change               
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2010-07-10 22:42 sruffell       Note Added: 0124463                          
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