Hey,
how come that JVM always uses only one from four cores ? If I run 2 or 3 Java apps, one core is employed on 100% and the rest is sleeping having nothing to do. Apps like Liferay, eclipse, sonatype nexus etc., multithreaded overlords.
There is plenty of free RAM also. ps and top shows what I just said, and entire system gets out of runtime suddenly like if all the cores were busy and there was no free RAM. I asked linux guys doing linux kernel and JVM, but I suppose there isn't straight answer.
java version "1.6.0_16" Java(TM) SE Runtime Environment (build 1.6.0_16-b01) Java HotSpot(TM) 64-Bit Server VM (build 14.2-b01, mixed mode)
linux - Slackware 64-bit x86_64 kernel 2.6.29.6