Re: mod_perl2 and SDBM-tied hashes

[Jonathan Vanasco <suppressed>]

On Jul 29, 2007, at 12:15 PM, Brian Reichert wrote:

> But, that contradicts the behavior I see with my command-line tool  
> demo:
> distinct processes with distinct tied hashes can sucessfully share  
> data
> through the sdbm.  :/
any reason why you're using sdbm ?  you might be better off with bdb,  
since it has that shared memory cache feature.


> > It's not the same hash, it's a hash at the same memory location in  
> > each of
> > your processes. If your process is deterministic and the hash is  
> > created
> > either in the apache parent or at the same point after forking,  
> > then it will
> > get the same memory address in each child.
are you sure about that?   i thought they were different in each  
child, and I thought if you access it via copy-on-write it'll move to  
a new space.


> If it's a factor:
>
> RedHat's apache2 RPM defaults to the prefork MPM.  If I try to use
> the worker MPM, I get a 'free(): invalidpointer' error.
you generally don't want to use worker under modperl, and you  
generlaly do want to use prefork.
The RedHat RPMs tend to be outdated,  especially for modperl.  You're  
often best suited building apache and modperl from source.