Re: pthread roadmap

[Marcus Brinkmann]

On Mon, Oct 07, 2002 at 05:01:24AM -0400, Roland McGrath wrote:
> I still have not read Neal's pthreads code, so I am just talking about the
> general case assuming everything is as billed.  If this libpthread hooks
> into libc the same way as cthreads does, and otherwise works with at least
> the functionality of cthreads (which ain't much), then there is no reason
> not to use it as the immediate transitional solution.  For user programs
> it's a no-brainer--it's better than nothing.

Right.  Neal, can you check in your pthread code into the Hurd CVS and
continue maintaining it there?  Then we can cut a new Debian tar file and
start compiling packages.

> For the Hurd servers, the requirements are different from normal programs
> written for pthreads.  The really sticky bit is the Hurd cancellation
> semantics, but that's mostly implemented in libc.

Right.  I hope Neal can comment on this point.

> If we have that, then I see no reason not to proceed with the switchover.
> The Hurd server code with pthreads+hurd-cancellation will look closer to
> what it will eventually look like than what it looks like now does.  The
> only reason not to switch is the first reason not to do anything: cthreads
> is well-worn and hasn't surprised us in a long time, and the new code
> always has the potential to make life more interesting in unplanned ways.
> I probably won't audit the code thoroughly, but if Marcus and Neal run
> pthreadsified Hurds and beat on them for a while and declare it good, I
> will be satisfied.

This is fair enough.  We are not in a hurry with such a transition. 
The L4 release is still a couple of months away, and there is no immanent
strong reason to move the Hurd code over, except the simplification that
people don't need to learn about cthreads anymore (they would still have to
learn about the cancellation stuff).

BTW, someone is already working on doing the transition, so another reason
to do this (if everything works out ok) is that somebody else does it for
us, which is the best reason I can think of ;)
 
> As to the likely future for the integrated glibc pthreads, I won't say much
> now.  It shouldn't be all that much work in the grand scheme on things.
> But as I have yet to actually get my ass in gear, it would be disingenuous
> to start estimating now when it might arrive at the various waystations.

Just as fair enough as well.
 
Thanks,
Marcus

-- 
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Marcus Brinkmann              The Hurd http://www.gnu.org/software/hurd/
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