GC performance tests?

Sat Nov 13 03:19:00 GMT 1999

Tom Tromey wrote:
> If you've been doing GC performance testing with gcj, could you send
> me a pointer to the code you're using to test it? I have most of the
> bitmap marking code written here, and I want to be able to test it
> once I have it finished...

Okay, here's a simple, synthetic, and un-scientific benchmark I threw
together a while back when I was playing with GC stuff. Its worth noting
that libgcj's results here are a lot more consistent now that we've
upgraded to the 5.0a4 collector. We're currently ~0 - 30% slower than
the IBM JDK on most of these, except on the one that calls finalizers,
where libgcj is significantly faster. Having to run lots of finalizers
seems to hit IBM pretty bad.
libgcj's GC does tend to grow a significantly larger heap than the JDK -
especially when allocating large objects [bigArrays()]. The heap grows
2-3X as large as with the IBM JDK on this one.
regards
 [ bryce ]