RFR: 8187033: [PPC] Imporve performance of ObjectStreamClass.getClassDataLayout()

[Kazunori Ogata]

Hi Peter,

Peter Levart <peter.levart at gmail.com> wrote on 2017/09/20 17:51:23:

> From: Peter Levart <peter.levart at gmail.com>
> To: Kazunori Ogata <OGATAK at jp.ibm.com>, Hans Boehm <hboehm at google.com>
> Cc: core-libs-dev <core-libs-dev at openjdk.java.net>
> Date: 2017/09/20 17:51
> Subject: Re: RFR: 8187033: [PPC] Imporve performance of 
> ObjectStreamClass.getClassDataLayout()
> 
> Hi Ogata,
> 
> Do you have a source for your benchmark to share? I might be able to 
> squeeze a little more from this approach but it would be easier if I 
could
> test variants right away and not bother you...
> 
> Regards, Peter
> 

Hi Peter,

The benchmark is GradientBoostingTree of Intel HiBench [1].  HiBench is a 
suite of programs using Hadoop or Spark, and GradientBoostingTree is a 
Spark program.  The source code (in Scala) is [2].  To build the code, you 
need Apache Spark.

The command line is equivalent to java -Xmx10g -D spark.master="local[4]" 
GradientBoostingTree <inputDir> 100, but what I actually use is a Java 
program that calls the main method and measures its execution time using 
currentTimeMills().

By the way, I'm running the benchmark on POWER8 machine.  Removing 
volatile won't change the performance on x86.


[1] https://github.com/intel-hadoop/HiBench
[2] 
https://github.com/intel-hadoop/HiBench/blob/master/sparkbench/ml/src/main/scala/com/intel/sparkbench/ml/GradientBoostingTree.scala


Regards,
Ogata