STINNER Victor <victor.stin...@haypocalc.com> added the comment: Quick benchmark: - fork(), execv(), waitpid(): 19081.1 ms - os.popen(): 25769.8 ms - subprocess.Popen(): 40025.8 ms - subprocess.Popen() patched: 26155.2 ms
I tested Python 2.7 (debug build) on Linux (Debian Sid) with a Pentium 4 (Hyperthreading, 2 fake cores), 2 GB of memory. Without the patch, subprocess is 55% slower than popen. With the patch, subprocess is 1% slower than popen. It is not a good news: subprocess should be faster before my benchmark tries Popen() without stdout=PIPE ;-) pitrou> I think your analysis is wrong. These mmap() calls are for pitrou> anonymous memory, most likely they are emitted by the libc's pitrou> malloc() to get some memory from the kernel. In other words pitrou> they will be blazingly fast. Are you sure? :-) Note that popen() is 35% slower than fork()+execv()+waitpid(). Patched subprocess is 37% slower than fork()+execv()+waitpid(). Try attached bench_subprocess.py script to get your own results. ---------- Added file: http://bugs.python.org/file20976/bench_subprocess.py _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue11314> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
