On 24 Nov 2006 09:03:41 -0800 [EMAIL PROTECTED] wrote: > Stefaan A Eeckels wrote: > > On 21 Nov 2006 13:02:14 -0800 > > [EMAIL PROTECTED] wrote: > > > > > The fact that it does this in Python code instead of C is the main > > > cause of the slowness. So, unless Python is changed to do this > > > in C, it's always going to be slow on AIX :-( > > > > I guess that the reason it's slow is that there are many > > descriptors to try and close. Reducing them using ulimit -n could > > improve the speed. > > > > AIX has a fcntl command to close all open file descriptors from a > > descriptor onwards: > > > > fcntl(3, F_CLOSEM); > > > > This of course should be used instead of the loop: > > > > 10 happens to be the value of F_CLOSEM (from /usr/include/fcntl.h). > > I've currently no access to an AIX system with Python, but it could > > be worth trying. > > Yes, very much worth it. F_CLOSEM is _so_ much better than the loop, > even in C. Using your brilliant suggestion, I now have a simple > patch to the python source that implements it for any OS that happens > to have the fcntl F_CLOSEM option.
The *BSDs and Solaris have "closefrom(3)" which does the same as F_CLOSEM in AIX. As with AIX, the speedup is dramatic when there are a lot of file descriptors to try and close. > It is below in its entirety. I believe I got the try: stuff correct, > but since I'm new to Python, I'd appreciate any comments. I'm no great Python specialist myself. I'll leave it to those better qualified to comment. > I have another patch to implement my os.rclose(x,y) method, which > would improve the speed of popenX() for the OSes that don't have > F_CLOSEM, by doing the close() loop in C instead of Python, but I > don't know if it would be as likely to be accepted as this probably > would be. > > Now, where do I send my proposed patch for consideration? The README file in the Python distribution has the following to say: Patches and contributions ------------------------- To submit a patch or other contribution, please use the Python Patch Manager at http://sourceforge.net/patch/?group_id=5470. Guidelines for patch submission may be found at http://www.python.org/patches/. Take care, -- Stefaan A Eeckels -- Never explain by malice what can be adequately explained by stupidity. However: Sufficiently advanced stupidity is indistinguishable from malice. -- http://mail.python.org/mailman/listinfo/python-list
