Is your CPU monitoring green too?

Defending some performance issues on a Windows based SQL Server 2008 R2 I took a look on CPU monitoring too. All green. Since months. That's good - I thought. Nagios as well as commercial tools like solarwinds comes up with average CPU usage, which means average acrosss single cores. In my case:

- 6 virtual Cores available
- 4 used by SQL Server at 90-100%
- 2 used by Windows at 2-5%

Makes an average around 60-70%. Fail. Now I'm looking for monitoring solutions per core. Any suggestions?

Java 7 to 8 Upgrade. Are you production ready?

A couple of days ago I upgraded one of our production environments from Java 7 to 8. All were tested before, so I took the challenge:

- Installation of Java 8
- Setting JAVA_HOME to new location
- Some work around RedHat JBoss EAP 6 middleware
- Restart of JBoss and Elasticsearch

Nice. JBoss and Elasticsearch started up. We're in production with Java 8!
After a couple of days CPU on production machines started to get exhausted by Java process. A heavy monitoring on JVM (using Jolokia) came up with a full JVM CodeCache. So the server started to compile just in time to serve requests.

CodeCache - if not set configured on JVM startup - comes with a default of 48 megabytes, which is too less for production environments. So a

-XX:ReservedCodeCacheSize=256M

helped to solve the problem. The new parameter was implemented in JBoss standalone.conf.bat. The CodeCache now levels around 60 megabytes.

ELK, ELG or ELKG?

Elasticsearch: Check. Logstash: Check. But what about Kibana vs. Grafana? My first impression: Quite similar.

After taking a closer look, Grafana looks much more handy for displaying timeline series of whatever data you've got. It's quite easy to add new data sources and I fell in love with those markers, which can be used to display single events throughout your time series. That's in fact great for getting an idea of e.g. error rate increases after application or module deployment.

I'm pretty sure I'll use both - Kibana and Grafana - along with each other to get the best of both tools.