database performance: Java Linux Databases: Kernels
There were no noticeable differences between kernel releases.
Newer kernels tend to perform marginally better than older ones,
but not sufficiently to justify an upgrade if the kernel you are using is well supported.
Various tests revealed minor scalability improvements, the most marking one was this multi-threaded test with Postgres and JDK 1.6:
From this graph, it seems that a scalability improvement was merged after 2.6.16.
But the picture is not uniform, and with MySQL updates, 2.6.16 does quite well:
