findSb: gradually rearrange the superblock list to bring frequently
accessed blocks closer to the front. This speeds up malloc/free
intensive programs because evidently those searches cause a lot of
cache misses (so cachegrind tells us). For perf/heap.c on P4
Northwood, this halves the run-time (!) from 85.8 to 42.9 seconds.
For "real" code (start/exit ktuberling) there is a small but
worthwhile performance gain, of about 2 seconds out of 95.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@5365 a5019735-40e9-0310-863c-91ae7b9d1cf9
1 file changed