NetBSD/java threading issues

[Francois Tigeot <ftigeot%wolfpond.org@localhost>]

On Thu, Dec 09, 2010 at 09:16:00PM +0100, Francois Tigeot wrote:
> On Wed, Dec 08, 2010 at 07:29:58PM -0500, Martin S. Weber wrote:
> > On Wed, Dec 08, 2010 at 08:25:22PM +0100, Francois Tigeot wrote:
> > > (...)
> > > some kaffe instances end up sitting in place and doing nothing. top and ps
> > > show a running kaffe-bin process, using 0% cpu.
> > 
> > Using scala (2.8.0) + lift (2.1) + jetty, you can achieve 
> > the same with ANY jre that runs on netbsd/i386
> 
> It seems there were some similar issues in the past on FreeBSD. I have found
> references to threading libraries and signal handling.

This old mail is quite enlightening. It mentions a 'java compiler stuck in
"pause" mode' :
http://lists.freebsd.org/pipermail/freebsd-threads/2003-June/000713.html

The FreeBSD guys changed their threading libraries during the years 2003-2004;
they went from an userland-only implementation of the pthread api (libc_r)
to two slightly different libraries using a M:N (libkse) or 1:1 (libthr)
threading model and making use of kernel SMP features.

The transition was quite painful, and java programs had exactly the same sort
of issues we are now seeing on NetBSD.

I just installed a NetBSD-4.01 system and had a go building wip/jdk15 on it:
it ran without trouble for 45 minutes. There were no threads stuck, the
bootstrap java compiler never failed.

One of the big changes of NetBSD 5 was (surprise, surprise) a brand-new
threading subsystem.
So, I think there's something slightly borked with the new threading system.
Unfortunately, I don't have enough system-level knowledge to find out more.

-- 
Francois Tigeot