Hello, On Sun, 22 May 2011 01:57:55 +0200 Artur Siekielski <artur.siekiel...@gmail.com> wrote: > 1. CPU cache lines (64 bytes on X86) containing a beginning of a > PyObject are very often invalidated, resulting in loosing many chances > to use the CPU caches
Mutating data doesn't invalidate a cache line. It just makes it necessary to write it back to memory at some point. > 2. The copy-on-write after fork() optimization (Linux) is almost > useless in CPython, because even if you don't modify data directly, > refcounts are modified, and PyObjects with refcounts inside are spread > all over process' memory (and one small refcount modification causes > the whole page - 4kB - to be copied into a child process). Indeed. > I'm not a compiler/profiling expert so the main question is if such > design can work, and maybe someone was thinking about something > similar? And if CPython was profiled for CPU cache usage? This has already been proposed a couple of times. I guess what's needed is for someone to experiment and post benchmark results. Regards Antoine. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
