From: Junio C Hamano Date: Sat, 24 Jun 2006 10:03:02 GMT Subject: PPC SHA-1 Updates in "pu" Message-ID: <7vwtb6yip5.fsf@assigned-by-dhcp.cox.net> In-Reply-To: <7vfyhv11ej.fsf@assigned-by-dhcp.cox.net> Junio C Hamano writes: > linux@horizon.com writes: > >> Well, I'm not sure it's worth this much trouble. Both of my PPC >> implementations are smaller and faster than the current one, >> so that's a pretty easy decision. The difference between them >> is 2-3%, which is, I think, not enough to be worth the maintenance >> burden of a run-time decision infrastructure. Just pick either one >> and call it a day. >>... >> Not that numbers are bad, but I think that until there's a real >> need for more than a single good-enough version per instruction set, >> this is excessive. > > OK. I somehow got an impression that your two versions had > quite different performance characteristics on G4 and G5 and > there was a real choice. If they are between a few per-cent, > then I agree it is not worth doing at all. If somebody has time and inclination, please try updated PPC SHA-1 from linux@horizon.com that is in "pu" (say make check-sha1) and report impressions. The first line from ./test-sha1.sh is the time output to hash 100MB and there should be bunch of OK output to verify the code hashes things correctly for inputs of various sizes.