Larry Hastings <la...@hastings.org> added the comment: > It doesn't have to. > Right now, it uses O(depth of the directory tree) FDs. > It can be changed to only require O(1) FDs
But closing and reopening those file descriptors seems like it might slow it down; would it still be a performance win? Also, I'm not a security expert, but would the closing/reopening allow the possibility of timing attacks? If so, that might still be okay for walk which makes no guarantees about safety. (But obviously it would be unacceptable for fwalk.) > Anyway, I think that such optimization is useless, because this > micro-benchmark doesn't make much sense: when you walk a > directory tree, it's usually to do something with the > files/directories encountered, and as soon as you do something > with them - stat(), unlink(), etc - the gain on the walking > time will become negligible. I'm not sure that "usually" is true here. I suggest that "usually" people use os.walk to find *particular files* in a directory tree, generally by filename. So most of the time os.walk really is quickly iterating over directory trees doing very little. I think 20% is a respectable gain, and it's hard for me to say "no" to functions that make Python faster for free. (Well, for the possible cost of a slightly more expensive algorithm.) So I'm +x for now. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue15200> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
