On Sun, 2007-04-29 at 01:42 +0000, Graham Dumpleton wrote: > On Apr 28, 6:40 am, Cliff Wells <[EMAIL PROTECTED]> wrote: > > On Fri, 2007-04-27 at 07:36 -0600, Orr, Steve wrote: > > > What are the advantages/disadvantages pros/cons to doing a proxy instead > > > of just usingmod_python? > > > > Typically, proxying is: > > > > 1. easier to setup thanmod_python > > 2. easier to upgrade Python (nomod_python/python version issues) > > Can you elaborate further on what the specific mod_python/python > versions issues are? Note that I ask this to learn what the problems > supposedly are and why it may be any more problematic than having to > recompile any third party C extension modules for Python which you may > have also installed into the Python site packages directory. Such > feedback would be useful because although people grumble about this > and use it as a reason against using mod_python, those same people > never actually come over to the mod_python mailing list to describe > the problems so that mod_python may if required be improved or so they > may be corrected in their understanding as to how things work.
I can give you a very specific example as I'll be dealing with it in the next couple of days ;-) A customer has an old Fedora (2 or 3) installation already running lots of stuff under Apache. mod_python (as shipped by Red Hat) is compiled against Python 2.3. Python 2.4 is installed but not used by mod_python. The client now wishes to run a Django application and requires 2.4. Most likely this will mean running two instances of Apache or (more likely), having to run Django as a fastcgi. Personally, I have no problem with running Django as a fastcgi, but it wasn't the client's first choice (and I believe mod_python to be the recommended deployment method for Django). Anyway, I'm not 100% certain there's anything that can be done by the mod_python project to resolve this particular type of issue (unless perhaps it would be possible to run multiple mod_python compiled against different versions of Python on the same Apache instance, but even then, we're still talking about lots of configuration, compiling, etc that simply aren't required for a proxied application). In short, the looser coupling between the webserver and the application that proxying provides gives all the usual benefits one might expect over a fully integrated solution and frankly, there isn't much downside as far as I can tell. > The only other problem area is transitioning to a newer version of > Python using the same system. That is, where you might want to be able > to run applications using different versions of Python. To do this > would mean running two distinct instances of Apache on the same box > but with different installations of mod_python/Python. Preferably if > doing this one should just perhaps use two different hosts. And this is my point: with proxying this isn't even remotely an issue. > > So except for the two quite specific issues noted above, are your > problems perhaps really just an issue of dependency management, > something that is going to occur for any software components and not > just mod_python itself? It occurs with any tightly coupled software system. Sometimes a tight coupling brings benefits that outweigh the issues you incur, but in this case I simply don't see the benefit of tightly integrating with the webserver. Performance benefits are usually negligible to non-existent over fastcgi or proxying and frankly I'm not sure what other benefits might even be claimed. > Any feedback would be most appreciated so the real problems can be > understood. Unfortunately when I have tried to dig into such claims in > the past, there is usually dead silence, so can never find out what > the real problems are so they can be addressed in mod_python if need > be. :-( Well, here you have it ;-) Regards, Cliff --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "pylons-discuss" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/pylons-discuss?hl=en -~----------~----~----~----~------~----~------~--~---
