Re: Do I get Physical Thread in Java?
Patricia Shanahan wrote:
zero wrote:
"Mike Schilling" <mscottschilling@hotmail.com> wrote in
news:VX1Gg.11618$kO3.5975@newssvr12.news.prodigy.com:
dimitrik107@hotmail.com wrote:
When you write Thread t = new MyThread(); r.start(), do you get a
new thread (you know like in Linux you call pthread_create() and
kernel gives you a new thread for running). Maybe java is
optimizing and JVM will not call pthread_create when you new your
thrread? If anyone know, please explain; thank you.
This is up to the JVM implementation. The Java standard decribess
how threads behave, but whether they're implemented with OS-level
threads, a lightweight threading package, or by having a
single-threaded interpreter round-robin among the active threads is
left open.
Furthermore, the whole point of java is not having to worry about
stuff like this. If you do, you're probably either using the wrong
tool (try C++) or going about your problem the wrong way. There may
be legitimate reasons to rely on this information in java, but I
can't think of any.
What about programs that need more than one second of CPU time per
second of elapsed time? Multiple OS threads can run on different
processors at the same time. A single OS thread can never get more
than one processor.
Yes. If the OP's question were qualified to be asking about a specific Java
implementation (including version), it could be answered in detail, and that
detail might be of real importance. It's a fallacy to conclude from "Java
can be used to write very portable applications" that "Java should *only* be
used to write very portable applications."
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