SqueakSource is down again

Philippe Marschall philippe.marschall at gmail.com
Sun Dec 23 23:36:25 UTC 2007


2007/12/23, Andreas Raab <andreas.raab at gmx.de>:
> Philippe Marschall wrote:
> > So which parts do we need to fix to make the Semaphore, Socket and
> > image freezing problems go away?
>
> For semaphores I'd recommend the fixes that I've posted over the year.
> For sockets I am not aware of any evidence that indicate a socket issue
> (we had a few issues that at first looked like sockets were related but
> turned out not) but I'd like to hear any evidence that points to sockets
> as the cause of problems. As far as I can tell the socket implementation
> is very robust right now. For image freezes -in particular in
> Squeaksource- you probably need to fix the concurrency issues in
> Squeaksource itself. The last time I checked the code was not robust
> enough by far against concurrent modifications (parallel commits etc).
>
> > As for scaling and production quality do you seriously expect me to do
> > this for free in my spare time?
>
> That depends on whether or not you seriously expect for example the VM
> people to fix the VM problems in their spare time for free. If the
> answer is yes, then the answer is yes.

Well I can honestly say that SqS is not production quality. It has no
serious persistence (the main installation on Squeak) and we make to
guarantees in this regard. The "storage" leaves several things to be
desired. We do write the .mcz to disk and back it put so there is
limit to the damage a broken image can cause. If you are uneasy with
this, don't use it. It has several stability issues which we believe
are not due to bugs in our code but in the Squeak-Kernel/VM. But we
never pretended otherwise, we never said there are no issues. We never
said "rock stable, no known bugs for years". If you ask on this list
if Squeak is production ready, how many of the VM maintainers are that
frank and say no?

> > We fixed performance the problems and now run seriously faster than
> > source.impara.de while being much bigger.
>
> That's great to hear. I wish you would have told me a couple of months
> ago how to achieve that when I was asking (repeatedly) the same questions.

What I was talking about is pure rendering performance. You get this
by loading the latest version, this was true several months ago as it
is now. If you use the Impara fork, well talk to the Impara guys. From
the description of your problems I got the impression  that the issues
you faced had much more to do with "persistence" and the issues we
face (general stability). As for persistence there is a Magma backend
which I pointed you at. AFAIK this has seen no action which I also
mentioned.

Cheers
Philippe



More information about the Squeak-dev mailing list