Re: concurrency, threads and objects
Robert Klemme wrote:
5ms as average starting time for a thread isn't really much.
That means windows can only create 400 threads in 2 seconds, compared to
linux 2.6 which creates 100,000 threads in 2 seconds. hats a big
difference. That makes me understand why people in this thread talks
about the performance hit of having large number of threads.
We are, though, comparing c thread calls to java thread calls, even
though java threads are native threads on both windows and linux in java 5.0
Additionally these numbers say nothing about execution efficiency of
threads in windows compared to linux.
I will have a look at you program and run it on my computer, in both
windows and linux, since there would be no no hardware difference. I
never thought it might be that big a difference between linux and
windows, actually I am not sure this difference can be correct. I know
Ingo Molnar of the linux kernel team is really good when it comes this
stuff, but microsoft can not be doing that bad here, we will see.
To test execution efficiency I will create a small test app which I will
run on both systems as well, just to get that angle. I will post my results.
> While I do agree
that thought has to be given to issues of memory consumption and CPU
usage during design of performance critical applications, overdoing it
is certainly doing more harm than good. Considering the overhead of one
object created per thread to be too much will definitively harm the
design of the application. And this is even more so true in Java where
the overhead of object creation on modern VM's is negligible.
I agree, it was an instinctive reaction that prompted me to start this
thread and I decided I wanted to know the answer. I like to know the
cost and consequence of doing things on one way compared to another, for
future reference.
I would be very carefully carrying over knowledge from a C environment
to a Java or other OO environment. While there are similarities and
general principles one must be aware of the platform and adjust to its
specifics.
I agree, but that does not preclude the chance that there might
something that can be learned from other platforms.
tom