Re: Get performance statistics?
Chris Uppal wrote:
Patricia Shanahan wrote:
Either way, I'm afraid it is going to be less convenient than my current
lifestyle - one makefile to control the runs, one Jar file to contain my
program, and it all works on my home system, works on my university
desktop, and runs dozens of jobs in parallel on a large grid computer.
Then it might be easier to use the Java-native JMX interfaces to the same (I
assume) features as JVMTI. See java.lang.management.ThreadMXBean.
I have never used it myself, so I don't know what lurking problems there may
be, but I'd guess it's worth spending a little time on it in the hope of
avoiding JVMTI or (worse) OS-specific JNI code.
Yes, that's the answer. I've tested the following sample program on a
couple of my MS-Windows system and on the grid:
package performance_stats;
import java.lang.management.ManagementFactory;
import java.lang.management.ThreadMXBean;
public class CPUTime {
public static void main(String[] args) {
System.out.println(getThreadCPUTime());
}
/** Get the CPU time used so far in this thread.
*
* @return CPU time in seconds
* @throws UnsupportedOperationException CPU time either not supported
* or not enabled.
*/
private static double getThreadCPUTime() throws
UnsupportedOperationException {
ThreadMXBean threadBean = ManagementFactory.getThreadMXBean();
long rawTime = threadBean.getCurrentThreadCpuTime();
if(rawTime == -1){
throw new UnsupportedOperationException("Thread CPU time capture
not enabled");
}
return rawTime/1e9;
}
}
It's pure Java, so I don't need to compile anything specially for the
Linux boxes, and it runs in my program, so I can put my stats in the
output file.
Thanks,
Patricia