hard memory limits

[Mike Meyer]

"Fredrik Lundh" <fredrik at pythonware.com> writes:

> Mike Meyer wrote:
>
>> > So why would Apple insist on setting unusably low process limits, when
>> > the others don't?
>>
>> You're making an unwarranted assumption here - that the OP wasn't
>> creating a large process of some kind.
>
> You need a special license to create large processes on a Mac?

No more so than on any other OS. What does that have to do with my
pointing out that the OP may have been creating a process that
exceeded the size normally allowed for non-administrator processes?
Any modern OS should have different groups of users with different
sets of possible maximum resource allocation - which only an
administrator should be allowed to change.

> I clicked on the google link that Bill posted, and noted that it wasn't
> exactly something that only affected a single Python user.  If some-
> thing causes problems for many different applications that run fine
> on other Unix systems, it's pretty obvious that the default OS X con-
> figuration isn't quite as Unixy as one would expect.

I didn't follow that link - I formulated my own google queery. While I
saw lots of things about vm_malloc, trying vm_malloc python turns up
nothing. Which seems to indicate that this is a relatively rare thing
for python users.

>> FWIW, OS X has a Mach kernel. The failing vm_malloc call listed in the
>> OP is a Mach call, not a Unix call.
> So has tru64.  I've done some serious Python stuff on that platform
> (stuff that included some really large processes ;-), and I never had
> any allocation problems.  But of course, that system was designed
> by DEC people...

Oddly enough, google just turned up a vm_malloc for VMS as well. I
wonder if that's where tru64 got it from - and if so how it got into
Mach?

There is something very non-unixy going on here, though. Why is
vm_malloc exiting with an error message, instead of returning a
failure to the calling application? I've seen other applications
include a FOSS malloc implementation to work around bugs in the
system's malloc. Maybe Python should do that on the Mac?

         <mike
-- 
Mike Meyer <mwm at mired.org>			http://www.mired.org/home/mwm/
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.