You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@harmony.apache.org by Marina Goldburt <ma...@gmail.com> on 2006/06/22 08:08:33 UTC
[classlib]hythreads implementation
Hi,
I've noticed such a strange thing when examined drlvm building process. The
drlvm replaces hythreads shared library with its own simple implementation
based on APR. The drlvm hythreads library exports less than 1/2
functions comparing with the original hythr.dll.
I thought the rest of functions are used by J9 VM, but replacing hythread
classlib implementation with the slightly modified drlvm one doesn't lead to
problems (all tests passed with j9 vm too).
So, the question : Why we have so much code in the hythreads module if
nobody neads it?
Marina
Re: [classlib]hythreads implementation
Posted by Andrey Chernyshev <a....@gmail.com>.
On 6/23/06, Tim Ellison <t....@gmail.com> wrote:
> Marina Goldburt wrote:
> > Hi,
> >
> > I've noticed such a strange thing when examined drlvm building process.
> > The drlvm replaces hythreads shared library with its own simple
> > implementation based on APR. The drlvm hythreads library exports less
> > than 1/2 functions comparing with the original hythr.dll.
>
> Yes, that is strange. Don't know why DRLVM would replace the classlib's
> thread library -- seems a bit impolite ;-)
Sorry about that :) Actually the issue was that the original hythread
library didn't work with the DRLVM - it required a thread to be
attached to the library because hythread monitors functions didn't
work otherwise. DRLVM has it's own threading code which wasn't
originally based on the hythread.
Then the DRLVM did a quick solution - provided it's own hythr.dll
which exposes to class libraries only those functions which are really
needed.
I agree it doesn't look too nice, though it helped to make it working
with the classlib quickly.
>
> > I thought the rest of functions are used by J9 VM, but
> > replacing hythread classlib implementation with the slightly modified
> > drlvm one doesn't lead to problems (all tests passed with j9 vm too).
>
> The IBM VME doesn't use Harmony's thread library (there is a remarkably
> similar library in the VM subdir called j9thr23).
>
> And,of course, if other VM's want to use their own thread library they
> are free to do so.
>
> > So, the question : Why we have so much code in the hythreads module if
> > nobody neads it?
>
> The honest answer is, not all the thread library code is needed by
> classlib -- but it forms a comprehensive library for any VM / classlib /
> tools development.
If I understand correctly, classlibs are mostly using hythread for
synchronization purposes. Could the class libraries do all the needed
synchronization at the Java level by natural Java means like
synchronized blocks? In this case they won't need extra libraries
except java.lang.Object or java.lang.Thread.
Another advantage could be that Java monitors are well known to Java
debuggers while locating problems with synchronization of the native
code may require additional tools and hence could be more difficult...
Thanks,
Andrey.
>
> Regards,
> Tim
>
> --
>
> Tim Ellison (t.p.ellison@gmail.com)
> IBM Java technology centre, UK.
>
> ---------------------------------------------------------------------
> Terms of use : http://incubator.apache.org/harmony/mailing.html
> To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
> For additional commands, e-mail: harmony-dev-help@incubator.apache.org
>
>
---------------------------------------------------------------------
Terms of use : http://incubator.apache.org/harmony/mailing.html
To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
For additional commands, e-mail: harmony-dev-help@incubator.apache.org
Re: [classlib]hythreads implementation
Posted by Marina Goldburt <ma...@gmail.com>.
Hi,
On 6/23/06, Tim Ellison <t....@gmail.com> wrote:
>
> The IBM VME doesn't use Harmony's thread library (there is a remarkably
> similar library in the VM subdir called j9thr23).
>
> And,of course, if other VM's want to use their own thread library they
> are free to do so.
And if the both VM use their own thread library, maybe it's more correctly
to let the library be a part of VM, not classlib?
> So, the question : Why we have so much code in the hythreads module if
> > nobody neads it?
>
> The honest answer is, not all the thread library code is needed by
> classlib -- but it forms a comprehensive library for any VM / classlib /
> tools development.
Actually, I'm interested in porting classlib to em64t platform and the
hythread library is the most compex part to port. And if the library isn't
used, I'm confused how can I port and test it?
Marina
Regards,
> Tim
>
> --
>
> Tim Ellison (t.p.ellison@gmail.com)
> IBM Java technology centre, UK.
>
> ---------------------------------------------------------------------
> Terms of use : http://incubator.apache.org/harmony/mailing.html
> To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
> For additional commands, e-mail: harmony-dev-help@incubator.apache.org
>
>
Re: [classlib]hythreads implementation
Posted by Tim Ellison <t....@gmail.com>.
Marina Goldburt wrote:
> Hi,
>
> I've noticed such a strange thing when examined drlvm building process.
> The drlvm replaces hythreads shared library with its own simple
> implementation based on APR. The drlvm hythreads library exports less
> than 1/2 functions comparing with the original hythr.dll.
Yes, that is strange. Don't know why DRLVM would replace the classlib's
thread library -- seems a bit impolite ;-)
> I thought the rest of functions are used by J9 VM, but
> replacing hythread classlib implementation with the slightly modified
> drlvm one doesn't lead to problems (all tests passed with j9 vm too).
The IBM VME doesn't use Harmony's thread library (there is a remarkably
similar library in the VM subdir called j9thr23).
And,of course, if other VM's want to use their own thread library they
are free to do so.
> So, the question : Why we have so much code in the hythreads module if
> nobody neads it?
The honest answer is, not all the thread library code is needed by
classlib -- but it forms a comprehensive library for any VM / classlib /
tools development.
Regards,
Tim
--
Tim Ellison (t.p.ellison@gmail.com)
IBM Java technology centre, UK.
---------------------------------------------------------------------
Terms of use : http://incubator.apache.org/harmony/mailing.html
To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
For additional commands, e-mail: harmony-dev-help@incubator.apache.org