On 04/08/2016 06:50 AM, Johnny Carlsen wrote: > Hi, > > After switching to the 2.6.32-573.22.1.el6.x86_64 kernel (CentOS 6) a few weeks ago I have noticed that my servers are now reporting a much higher idle load. > > The servers are being monitored with Zabbix, and there is a clear difference between the older kernel 2.6.32-573.12.1 and the newer 2.6.32-573.12.1. > > I can see the problem on both physical and virtual servers. > > You can see the Load Average chart here from one of our servers: > http://imgur.com/U1eihMX > > The server is pretty much idle all the time, but the load average increased from 0.001 to 0.300 when updated to the new kernel. > > Is anyone else seeing the same behavior? This is one of the fixes listed on the errata page: "Due to prematurely decremented calc_load_task, the calculated load average was off by up to the number of CPUs in the machine. As a consequence, job scheduling worked improperly causing a drop in the system performance. This update keeps the delta of the CPU going into NO_HZ idle separately, and folds the pending idle delta into the global active countwhile correctly aging the averages for the idle-duration when leaving NO_HZ mode. Now, job scheduling works correctly, ensuring balanced CPU load. (BZ#1300349)" From: https://rhn.redhat.com/errata/RHSA-2016-0494.html No idea if that is impacting the load shown on your machine .. maybe someone has some ideas. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: OpenPGP digital signature URL: <http://lists.centos.org/pipermail/centos/attachments/20160408/8588e087/attachment-0005.sig>