Javalobby - Comments for "What Java IDE VM arguments do YOU use?"

Im running Windows XP SP2 on

robsinner — Fri, 29 Feb 2008 18:31:35 -0500

Im running Windows XP SP2 on Dell Latitude D820 which has 2GB of Ram and Dual Core 1.66Mghz Processor.

My eclipse .ini settings are:

-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.XXPermSize
128m
-vmargs
-Xms128m
-Xmx768m
-XX:+UseParallelGC

Also recently I read these posts and turned off paging in windows and my ide performance has improved and I have had no wierd other problems with out of memory errors or anything like that.

Hi Fred,Great question!

jimbethancourt — Tue, 29 Jan 2008 10:18:54 -0500

Hi Fred,

Great question! The -XX:+UseParallelGC flag enables what is known as the Throughput Collector, and is described on the Garbage Collection Tuning Guide:

The throughput collector is a generational collector similar to the serial collector but with multiple threads used to do the minor collection. The major collections are essentially the same as with the serial collector. By default on a host with N CPUs, the throughput collector uses N garbage collector threads in the minor collection.

Cheers,
Jim Bethancourt
President, Houston Java Users Group
Technical Architect, ROME Corporation

Now, I will not mention

fg82183 — Sat, 26 Jan 2008 21:55:14 -0500

Now, I will not mention tha tI just swiched to a dual core cpu workstation..whooops :)

What does -XX:+UseParallelGC do?? as I have yet ot use that one..

I imagine turning off paging on non dual core cpu systems is effective..on dual core you do not even have to bother..:)

Fred Grott(aka shareme) sometimes a JavaZone(JavaLobby) and EclipseZone contributor. Top visited blog on Jroller.com at: http://www.jroller.com/shareme/

I used to use

tim — Wed, 23 Jan 2008 13:10:05 -0500

I used to use -XX:CompileThreshold=400 - this will slow down IDE startup mightily, but performance is snappier once it is up and running.

-Tim

I hate to nag, but since I

zvikico — Wed, 23 Jan 2008 02:10:24 -0500

I hate to nag, but since I switched over to Mac OS X I don't bother anymore. I'm doing Eclipse plug-in development. It is not uncommon for me to have 3 instances or Eclipse running at the same time, not to mention everything else running in the backgournd (even virtualized Windows Vista). Works like a charm. I really don't care.

My hardware: MacBook Pro 2.4 GHz C2D, 2GB Memory.

If you're on Windows,

edgeztv — Mon, 21 Jan 2008 19:22:59 -0500

If you're on Windows, turning off the system paging file makes the most difference in IDE performance.

Don't bother trying the GC options that the OP mentioned. They won't make any difference if your paging file is being used.

I tried tuning my IntelliJ params for months without much improvement and then realized that the biggest enemy of Java apps on Windows is the paging file. It really makes a HUGE difference. The reasons for that take a while to explain. Just try it for yourself and see. (You should have 1.5+ Gigs of RAM for this)

Here's how:

http://www.codinghorror.com/blog/archives/000422.html

I have read that concurrent

MarisO — Mon, 21 Jan 2008 18:43:50 -0500

I have read that concurrent low pause (CMS) collector (+XX:UseConcMarkSweepGC) is better than The Throughput Collecto. For example, here http://www.coldfusionmuse.com/index.cfm/2005/10/28/jvm.gc. Also NetBeans configuration FAQ recommends to use CMS

For IntelliJ IDEA, you

ann — Mon, 21 Jan 2008 12:41:00 -0500

For IntelliJ IDEA, you might also want to play with the "-server" option. It will most likely affect the startup, but the overall performance may improve.

As usual, fully depends on the environment... :-)

Matt and I almost always

rick — Mon, 21 Jan 2008 11:51:35 -0500

Matt and I almost always load IntelliJ IDEA and Eclipse up with more memory than they default to. This is actually a bit of a pain to do on IDEA for Macintosh because you have to go into the package file and find the options in an obscure place. Worse, they don't persists, so when you put in an updated version of IDEA you lose the settings and need to remember to do it again.

If we are simply not doing it right, then I would love to know the preferred method.

Rick