Has anyone ever had code in Python, that turned out not to perform fast enough?
I mean, you were forced to choose another language because of it?
We are investigating using Python for a couple of larger projects, and my feeling is that in most cases, Python is plenty fast enough for most scenarios (compared to say, Java) because it relies on optimized C routines.
I wanted to see if people had instances where they started out in Python, but ended up having to go with something else because of performance.
Thanks.
I've been working for a while now, developing an application that operate on large structured data, stored in several-gigabytes-thick-database and well, Python is good enough for that. The application has GUI client with a multitude of controls (lists, trees, notebooks, virtual lists and more), and a console server. 
We had some performance issues, but those were mostly related more to poor algorithm design or database engine limitations (we use Oracle, MS-SQL, MySQL and had short romance with BerkeleyDB used for speed optimizations) than to Python itself. Once you know how to use standard libraries (written in C) properly you can make your code really quick. 
As others say - any computation intensive algorithm, code that depends on bit-stuffing, some memory constrained computation - can be done in raw C/C++ for CPU/memory saving (or any other tricks), but the whole user interaction, logging, database handling, error handling - all that makes the application actually run, can be written in Python and it will maintain responsiveness and decent overall performance.
Python Performance - have you ever had to rewrite in something else?