[CentOS] Kernel update = slower ?

[Johnny Hughes]

On Thu, 2006-06-01 at 15:54 -0400, Sam Drinkard wrote:
> This is really strange.  Day before, I updated the machine here (x86_64) 
> and all went normal.  I rebooted, and everything came back just as I 
> expected.  Next morning, I noticed one of my jobs during the night had 
> finished, but finished late by about 8 or 9 minutes.  I really didn't 
> think much of it, but after looking at jobs running today, I'm seeing 
> the same thing.  Processes that used to take 3.75 hours to complete are 
> now taking 4 hours.  ( I have cron jobs that were running to process the 
> data after the main run, and they busted)  Nothing has changed in the 
> way the model runs, and there have been no changes to input data or any 
> other parameter that would cause a longer runtime.  So, the question is, 
> did something change in the kernel that would make the machine run 
> slower?  I do have threading turned on in the bios, and all 4 cpu's are 
> shown via dmesg.  In fact, I looked at the dmesg output after a reboot 
> and due to another message about losing clock tics, I just checked that 
> I had not encountered the same.    Short of rebooting back into the 
> previous kernel, is there any way to tell if something is slowing the 
> box down?
> 

There is an issue with VM configuration that might cause swapping and
that COULD slow the machine down.

However ... since it was an "Important kernel securtity update" ... I
would at least read this before booting into the old kernel:

https://rhn.redhat.com/errata/RHSA-2006-0493.html

Here is details concerning the VM issue:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=188141

I reality that bug started last kernel ... but I have noticed more on
this one.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
URL: <http://lists.centos.org/pipermail/centos/attachments/20060601/d33223fc/attachment.sig>