-Xcomp

Performance Tuning
#1

Just reading some stuff over at TopCoder…
http://www.topcoder.com/rtables/viewThread.jsp?forum=64101&thread=232826&mc=27

and came across this statement:

[quote]From the conversations I’ve read on -Xcomp - it’s pretty much like running a C++ program - you have a static compile up front and run the resulting code (it will NOT attempt any further enhancements nor back-out of bad guesses).
[/quote]
Which led me to ponder… Does -Xcomp inline anything? Can methods be inlined later during the run if you use -Xcomp.

Which comes down to: Is -Xcomp a valid way to benchmark or is it going to give you something too different from what you would get with a ‘warmed up’ mixed mode run?

#2

He’s completely wrong.

All -Xcomp does is reduce the Hotspot threshold for compilation to 0 (compile each method immediately.)

Otherwise ist just like any other compilation Hotspot does.

Moral: Don’t believe everything you read, especially on the web. (see definition below)

Def: The World Wide Web
The greatest medium ever developed to allow those who know nothing to inform those who know less… :wink:

#3

I did doubt the accuracy of that info, which is why I brought it up here… we all know that this side of the web is 100% accurate :wink:

#4

Well 98.6% accurate…

I’m wrong every so often. And I like to think that, once its proven, I’m man enough to accept it :slight_smile:

But here I’m very very sure he’s wrong. :slight_smile: