Re: High CPU utilization on RHEL5.6/CentOS5.6

Neither install is running within VMWare.

On Mon, Jul 25, 2011 at 5:55 PM, Fred Moyer <[email protected]> wrote:
> This may not be related, but when I was working with Centos 5 in a
> Vmware environment, I ran into an issue of high cpu since the default
> clock rate with Linux 2.6 is 1000Hz.  I changed to a 100Hz clock rate
> and got much lower cpu usage.
>
> I'm not sure if that is your issue, perhaps FC14 was using less than a
> 1000Hz clock rate.  You might try a tickless kernel, or dig further
> into what clock rate your kernel is using.
>
> I don't know where the authoritative source for this information is,
> but here's what I found with a search:
>
> http://yate.null.ro/pmwiki/index.php?n=Main.YateAndVMWare
>
> On Mon, Jul 25, 2011 at 3:43 PM, Christopher Stanton
> <[email protected]> wrote:
>> I have a MJPEG streaming system which uses mod_perl in the web
>> interface to supply the final stream to the client.
>>
>> I am seeing high cpu utilization under RHEL5.6 which I don't see on
>> FC14. We are talking sub 10% on FC14 vs 80% on EL5. This is on
>> different hardware, but not that different. And on EL5 the httpd
>> session is way higher (cpu wise) than the supplying proxy. On FC14 on
>> my test rig I see (for a 25fps stream) 15-18% CPU for the proxy which
>> can handle multiplexing etc and 5.5-8% for the mod_perl httpd session.
>>
>> I think this is an issue with that platform, but I haven't seen
>> any/many reports. Does anyone have a sec to look at the source? I
>> don't think I have implemented this is a horrible inefficient way but
>> who knows. It is true, I could have byte markers and then know the
>> size of the JPEG I am expecting rather than just splitting on the
>> boundary field, but in tests (and production) it seemed to work ok.
>>
>> http://svn.codaxus.com/flexTPS/2.x.x/trunk/portal/2.4.x/site/perl/nph-mjpeg_stream.pl
>>
>> Any comments or critiques would be appreciated,
>> Christopher
>>
>> ----------------------------------------------------------------------
>>
>> On FC14:
>> Requires: httpd >= 2.2.17-1
>> Requires: mod_perl >= 2.0.4-11
>> Requires: mod_ssl >= 1:2.2.17-1
>> Requires: perl >= 5.12.3-141
>> Requires: perl-CGI >= 3.51-1
>> Requires: perl-Digest-SHA1 >= 2.12-4
>> Requires: perl-XML-Filter-BufferText >= 1.01-9
>> Requires: perl-XML-Simple >= 2.18-7
>> Requires: perl-XML-Validator-Schema >= 1.10-5
>> Requires: perl-Tree-DAG_Node >= 1.06-8
>> Requires: perl-LDAP >= 0.40-2
>> Requires: perl-Crypt-SSLeay >= 0.58-1
>> Requires: ffmpeg >= 0.6-4
>>
>> On EL5:
>> Requires: httpd >= 2.2.3-45
>> Requires: mod_perl >= 2.0.4-6
>> Requires: mod_ssl >= 2.2.3-45
>> Requires: perl >= 5.8.8-32
>> Requires: perl-Digest-SHA1 >= 2.11-1
>> Requires: perl-XML-Filter-BufferText >= 1.01
>> Requires: perl-XML-Simple >= 2.14-4
>> Requires: perl-XML-Validator-Schema >= 1.10-1
>> Requires: perl-Tree-DAG_Node >= 1.06
>> Requires: perl-LDAP >= 0.33-3
>> Requires: perl-Crypt-SSLeay >= 0.51-11
>> Requires: ffmpeg >= 0.6.1-1
>>
>