Testing whether Xlib threading support works in XORG-RELEASE-1branch...

[Roland Mainz]

Jim Gettys wrote:
> > > >While I don't doubt there could be problems, you should
> > > >be aware in the past that Mozilla's threading itself was badly
> > > >broken (IIRC, at the time wasn't even actually calling Xlib's thread
> > > >initialization at all; this was in late Netscape days).  I
> > > >remember a very frustrating debugging session on the
> > > >phone with Keithp where we ended up having to conclude we
> > > >couldn't fix it (it being Netscape, without source available),
> > > >and that the fault was 100% Netscape's.
> > >
> > > Mozilla only does drawing from the main thread, so it's not like we're
> > > even pushing that code very hard.  Mozilla's threading doesn't have any
> > > serious issues that I know of right now.  I don't know what roland is
> > > seeing.
> >
> > See my other reply here... I was never talking about bugs in Mozilla, I
> > was interested that the X11 peopple test their Xlib and X extension
> > libraries against a real-world application (e.g. mozilla) with Xlib
> > threadsafe mode enabled to check whether this works now or not... in the
> > past that part of Xlib was simply unuseable since the implementation
> > assumed that it is safe to lock a mutex recursively. Xfree86 people did
> > some work on that before V4.4.0 was released and my patch for Mozilla
> > was mainly ([1]) to test whether the fixes are complete or whether more
> > work is required.
> >
> > [1]=there is the idea to run plugins in a seperate thread but that
> > cannot be implemented in the near future (>=2 years) since the fixes
> > have to spread first over all Unix/Linux distributions before we can
> > even think to make any use of that.
>
> I guess the answer is that little active testing gets done;
> this is not a healthy state. My point is just that Mozilla is
> intimidating enough to have inhibited its use in this area.
> 
> This may no longer be a viable concern, as mozilla's
> release engineering has improved greatly and it can be built
> by mere mortals these days.

Erm... the test code I added to Mozilla is available in the OFFICIAL
mozilla.org release builds for Mozilla1.7b, available for download from
http://www.mozilla.org/releases/
You do NOT have to build it. Just run Mozilla with the XORG shared libs
without MOZILLA_X11_XINITTHREADS set. If that works (it should since
this is the "default") then set MOZILLA_X11_XINITTHREADS=1 and run
Mozilla again. If Mozilla still works then everything is OK. If Mozilla
hangs a bug should be filed and maybe considered as release blocker.

> When Keith and I were burned by it, it required a Netscape/mozilla
> wizard, and our last experience
> was frustrating and resulted in just determining that the
> hang we were seeing was a Netscape bug, and that no one at
> Netscape was interested in helping track that bug down at the time.
> 
> We can easily believe there are bugs....

... and I'd like to catch&&squish them all. Or put these insects into
the next available microwave... =:-)
Did anyone do some testing against XORG-RELEASE-1 yet (I hadn't time for
that yet... I am still recovering slowly from my last month's
pneumonia... ;-() ?

----

Bye,
Roland

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