a couple of years back we did a lot of experimentation between sun's
vm and jrocket. We had initially assumed that jrocket was going to
scream since thats what the press were saying. In short, what we
discovered was that certain jdk library usage was a little bit faster
with jrocket, but for core vm performance such as synchronization,
primitive operations the sun vm out performed. We were not taking
account of startup time, just raw code execution. As I said, this was
a couple of years back so things may of changed.
C
On May 7, 2009, at 2:17 AM, Grace wrote:
I am running the test on 0.18.1 and 0.19.1. Both versions have the
same
issue with JRockit JVM. It is for the example sort job, to sort 20G
data on
1+2 nodes.
Following is the result(version 0.18.1). The sort job running with
JRockit
JVM took 260 secs more than that with Sun JVM.
-----------------------------------------------
|| JVM || Completion Time ||
-----------------------------------------------
|| JRockit || 786,315 msec ||
|| Sun || 526,602 msec ||
-----------------------------------------------
Furthermore, under 0.19.1 version, I have set the reusing JVM
parameter as
-1. It seems no improvement for JRockit JVM.
On Thu, May 7, 2009 at 4:32 PM, JQ Hadoop <jq.had...@gmail.com> wrote:
I believe Jrockit JVM have slightly higer startup time than the SUN
JVM;
but
that should not make a lot of difference, especially if JVMs are
reused in
0.19.
Which Hadoop version are you using? What Hadoop job are you
running? And
what performance do you get?
Thanks,
JQ
-----Original Message-----
From: Grace
Sent: Wednesday, May 06, 2009 1:07 PM
To: core-user@hadoop.apache.org
Subject: Is there any performance issue with Jrockit JVM for Hadoop
Hi all,
This is Grace.
I am replacing Sun JVM with Jrockit JVM for Hadoop. Also I keep all
the
same
Java options and configuration as Sun JVM. However it is very
strange that
the performance using Jrockit JVM is poorer than the one using Sun,
such as
the map stage became slower.
Has anyone encountered the similar problem? Could you please give
some
advise about it? Thanks a lot.
Regards,
Grace
