Re: Update to Solr 6 - Amazon EC2 high CPU SYS usage

2017-04-27 Thread Shawn Heisey
On 4/27/2017 3:03 AM, Elodie Sannier wrote:
> We have migrated from Solr 5.4.1 to Solr 6.4.0 on Amazon EC2 and we have
> a high CPU SYS usage and it drastically decreases the Solr performance.
>
> The JVM version (java-1.8.0-openjdk-1.8.0.131-0.b11.el6_9.x86_64), the
> Jetty version (9.3.14) and the OS version (CentOS 6.9) have not changed
> with the Solr upgrade. 

I can almost guarantee that this is the issue you are experiencing:

https://issues.apache.org/jira/browse/SOLR-10130

Upgrade to 6.4.2 or later.

Thanks,
Shawn



Update to Solr 6 - Amazon EC2 high CPU SYS usage

2017-04-27 Thread Elodie Sannier

Hello,

We have migrated from Solr 5.4.1 to Solr 6.4.0 on Amazon EC2 and we have
a high CPU SYS usage and it drastically decreases the Solr performance.

The JVM version (java-1.8.0-openjdk-1.8.0.131-0.b11.el6_9.x86_64), the
Jetty version (9.3.14) and the OS version (CentOS 6.9) have not changed
with the Solr upgrade.

Using "strace" command we have found a lot of "clock_gettime"
(gettimeofday) calls when Solr is started.

The clocksource on Amazon VMs is "xen" and, according to this web site,
it impacts the system calls:
https://blog.packagecloud.io/eng/2017/03/08/system-calls-are-much-slower-on-ec2/


We have updated the clocksource to "tsc" and it fixes the issue.

Is there a change between Solr 5.4.1 and 6.4.0 that would trigger many
more gettimeofday calls done by the JVM ?

Elodie

Kelkoo SAS
Société par Actions Simplifiée
Au capital de € 4.168.964,30
Siège social : 158 Ter Rue du Temple 75003 Paris
425 093 069 RCS Paris

Ce message et les pièces jointes sont confidentiels et établis à l'attention 
exclusive de leurs destinataires. Si vous n'êtes pas le destinataire de ce 
message, merci de le détruire et d'en avertir l'expéditeur.