JVM performance Linux versus AIX/Solaris

[thomhashi]

Hi there,

I have recently installed a custum bluid java application on serveral
of platforms and was amazed with the difference in performance.
The Linux system pushed the CPU to the limit and gave twice the
performance compared to Solaris and AIX systems which only used 50% of
their CPU power.

avg response times

AIX - 2586 ms / CPU load 50% / 666 mhz cpu 512mb
Solaris - 2486 ms / CPU load 50% / 1000 mhz cpu 2048mb
Linux - 1344 ms / CPU load 100% / 800 mhz cpu 2048mb

The funny thing is the application only uses 50% of the CPU capacity
under AIX and Solaris while under Linux the CPU load is much higher.

Does anyone seen this type of behaviour before?
I suspect it has something to do with threads, under AIX and Solaris 1
single JVM does al the processing while and opens a lot of threads,
Linux starts 46 JVM instances (processes).

Regretfully the software company doesn't give the source free and we
are stuck with this performance issue.

Any sugestions are apreciated.

t.

 

[Gordon Beaton]

I suspect it has something to do with threads, under AIX and Solaris
1 single JVM does al the processing while and opens a lot of
threads, Linux starts 46 JVM instances (processes).

Those are threads. The Linux threading model is different than on the
other platforms, and individual threads appear in the process table.
They share the same process space.

/gorson

 

[Nils O. =?iso-8859-1?Q?Sel=E5sdal?=]

Hi there,

I have recently installed a custum bluid java application on serveral
of platforms and was amazed with the difference in performance.
The Linux system pushed the CPU to the limit and gave twice the
performance compared to Solaris and AIX systems which only used 50% of
their CPU power.

avg response times

AIX - 2586 ms / CPU load 50% / 666 mhz cpu 512mb
Solaris - 2486 ms / CPU load 50% / 1000 mhz cpu 2048mb
Linux - 1344 ms / CPU load 100% / 800 mhz cpu 2048mb

The funny thing is the application only uses 50% of the CPU capacity
under AIX and Solaris while under Linux the CPU load is much higher.

Does anyone seen this type of behaviour before?
I suspect it has something to do with threads, under AIX and Solaris 1
single JVM does al the processing while and opens a lot of threads,
Linux starts 46 JVM instances (processes).

No, you just see them as "processes" in "top", "ps" and similar.
They are really threads.

Regretfully the software company doesn't give the source free and we
are stuck with this performance issue.

Any sugestions are apreciated.

There are lots of things For instance, how fast harddrives do they
have ? , Which java version did you test on ? There can also be small
variations in how the system measures average CPU load, atleast for
a small time slice.
It was no surprice that linux came out best though.