Not to mention, we are very young here, and the usual quote about
optimization applies, so I'd say we not worry too much about
performance just yet.
Do note, however, that committers can get a free Open Source license
for YourKit just by asking them. Same goes for other tools, too, like
IntelliJ, etc.
-Grant
On Mar 11, 2008, at 4:15 AM, Dawid Weiss wrote:
Try turning on verbose gc.
Benchmarking is a difficult stuff, really. Much harder than folks
usually consider it. Looking at GC, for example, you have to be
aware not only of the GC type used (and its settings), but also of
the machine the benchmarking is run on.
In Jason's case, if he's running 64-bit server JVM on a multi-core
machine, then the JVM is using a parallel GC and is effectively
running behind the scenes :)
You can also try using YouKit profiler -- it's does really good job
at showing heap/ GC usage.
I am far from being an expert in JVM architecture, but I think boxed
primitive types do have very special optimization at low-level and
since so produce very little overhead. Also, the collections inside
JDK have been optimized heavily since their initial releases. Much
like reg-exes: we recently compared a code that used Pattern class
and hand-crafted parsing code. The hand-crafted code was 100%
faster, but much longer and more difficult to read.
Dawid
