Michael Bayer wrote: > > On Sep 4, 2008, at 12:40 AM, gniquil wrote: > >> Hi All, >> >> I am doing some work with xmlrpc. One thing I realize is that whenever >> I pass dict(row) through xmlrpc, I get an key-ordered struct. But this >> isn't what i really want. What I want is ordered by insertion or the >> original list order. This led me to look at the util.ordereddict >> implementation, which is pure python, which is slow. I looked around >> and found this: >> >> http://www.xs4all.nl/~anthon/Python/ordereddict/ >> >> which is a c-implementation. At the bottom of the page, there are >> performance tests. It's much faster. I've got some pretty gigantic >> tables to pass around, which i think this would really help. Hopefully >> this could somehow find itself into next official python. But before >> that, we can use this or we can just incorporate it somehow in >> sqlalchemy...as a suggestion. >> > > the problem with saying "utility class X is slow, therefore use Y" is > that you haven't evaluated if the slowness of X is really impacting > the performance of SQLAlchemy overall in a negative way. I think if > you ran some profiling results you'd see that OrderedDict calls make > up a miniscule portion of time spent for doing all operations, so an > external dependency is not necessarily worth it in this case (though > it may be). I have some vague recollection that our own ODict does > some things the native one does not but I'd have to dig back into the > code to remember what they were. If our own ODict could be swappable > with ordereddict, we could at least try to import it then fall back to > our own (this is what it would look like if ordereddict were > introduced into python core anyway).
fwiw i spiked this out a while back (just before 0.4.0, maybe), and swapping in a native ordered dict was a very marginal speed improvement, and most of it was in metadata setup rather than runtime speed. as svil said, it's easy to try this out by monkeypatching in alternate implementations and then hitting the various profiling and speed tests in the test suite. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
