The JVM has about a hundred options for fine tuning garbage
collection. Have you tried turning on the JVM GC logging and looking
at what it's really doing?
- Elliott
On Jan 16, 2009, at 1:05 PM, Edmund Kohlwey wrote:
Good questions!
Right now one of my biggest concerns is actually memory usage. The
application frequently garbage collects, and despite my attempts to
reduce memory consumption I still find that the rate of (and penalty
incurred by) GC'ing is excessive, and may become unacceptable. I
realize that there probably won't be much that I can do to reduce GC
rate, but if a different JVM could decrease the penalty that would
be of significant value.
Dustin J. Mitchell wrote:
"We should forget about small efficiencies, say about 97% of the
time:
premature optimization is the root of all evil." (Hoare)
Ed wrote, "I am ... concerned about performance of the JVM...."
Well,
JVMs are very slow at some things, and very fast at others. By
compiling with gcj, you gain in some areas (to varying degrees over
various JVM's) while losing in others (gcj can, in some instances,
end
up compiling down to a bunch of subroutine calls to implement complex
operations, which is a loss over optimized JIT JVMs).
So out come the old saws, "what do you mean by performance" and "how
are you going to measure it?" That's really the only way to get to
the bottom of this question.
Dustin
