[ removing autoconf list -- please Cc: me on replies ] * Eric Blake wrote on Mon, Jun 05, 2006 at 12:09:07AM CEST: > According to Ralf Wildenhues on 6/4/2006 2:56 PM: > > * Eric Blake wrote on Sun, Jun 04, 2006 at 05:40:05AM CEST: > >> m4: lookup mode 0 called 229730 times, 557880 compares, 348729 misses, > >> 4672624 bytes
> > [ coreutils ] > >> m4: lookup mode 0 called 2526799 times, 9834148 compares, 7470505 misses, > >> 84329947 bytes > > > > This is still not bad at 3.9 compares per call. > > But it can be made better - 3.9 strcmp per call is somewhat reduced by > increasing the number of hash buckets. The problem is whether that is the > hotspot in m4; and my experiments confirm what Paul found, that it was > slightly noticeable, but not earth-shattering. Even if it were a hotspot, you'd have to weigh the larger hash table against the larger memory set now, and whether it may just cause more cache misses. I still maintain that more may be bought by evaluating and rewriting some Autoconf macros; eliminating multiple recursion, where present, and maybe pushing some of the larger quadratically growing strings to using lists of macros, and expanding them only very late, or so. No, I can't prove this ATM, sorry, it's merely the impression I got after this: http://lists.gnu.org/archive/html/libtool-patches/2005-10/msg00161.html But this kind of work certainly needs to wait until after 2.60. Cheers, Ralf _______________________________________________ M4-patches mailing list [email protected] http://lists.gnu.org/mailman/listinfo/m4-patches
