Customer has reported a very poor performance with JBoss and JDK 8. When they turned the -XX:+TieredCompilation flag off they saw a dramatic improvement in JBoss server performance.
In this particular case it was the JCA subsystem that was most affected with getConnection() times varying from 1ms to 540ms. All other factors (like GC for example) have been eliminated). Once the flag has been turned off the getConnection() was performing consistently within the requirements.
They argue we should turn this flag off by default. The JDK 8 turns it on by default.
We used java 1.8.0_121 with perf tests in 6.4.16 CP testing.
TieredCompilation is not explicitly set in any perf test.
Thanks Jirko, 1.8.0_121 means TieredCompilation on by default.
Could you please compare 1.8.0_121 against 1.8.0_<20 or against 1.8.0_121 with TieredCompilation off?
Any news, Jirko?
There is a difference in my performance tests.
A response time is cca 1600 ms with 300 clients when is set -XX:-TieredCompilation.
The response time is cca 1800 ms with 300 clients when is set -XX:+TieredCompilation.