[MUD-Dev] [Java] multithreading: update and a question

[Vadim Tkachenko]

Hello,

Just read the article about Java/Solaris implementation of
multithreading and have some questions.

Okay, they say, there are 3 MT models:

one-to-one: one user thread corresponds to one kernel thread, this
solution is rather heavyweight.

many-to-one: all the user thread map to one kernel thread (process),
this has the obvious drawback - it's not possible to utilize the
multiprocessor architecture properly.

many-to-many: there are N user threads and M kernel threads, and the
intermediate layer which maps the threads which require processor time
to the actual kernel threads. Obviously, this seems to be the best way
around, and the article claims that Solaris is the only OS which
supports this kind of thing (they say Windows, OS/2 and AIX have
one-to-one model).

Any comments about this? What I think about is someone mentioning the
concept of having a thread pool where the threads can be reused, but if
the case is many-to-many, this will just create the unnessessary
overhead (Solaris only).

Please consider this as a technical question, not the OS war.

I don't have the URL handy, this is a PDF document somewhere on Solaris
(not Java) site.

--
Still alive and smile stays on,
Vadim Tkachenko <vt at freehold.crocodile.org>
--
UNIX _is_ user friendly, he's just very picky about who his friends are