From owner-freebsd-questions Mon Nov 15 22:23:54 1999 Delivered-To: freebsd-questions@freebsd.org Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.40.131]) by hub.freebsd.org (Postfix) with ESMTP id 911B414D83 for ; Mon, 15 Nov 1999 22:23:50 -0800 (PST) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.9.3/8.9.2) with ESMTP id HAA23591; Tue, 16 Nov 1999 07:23:03 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: mi@aldan.algebra.com Cc: questions@freebsd.org Subject: Re: -lmd's MD5File() In-reply-to: Your message of "Mon, 15 Nov 1999 18:35:08 EST." <199911152335.SAA31130@misha.cisco.com> Date: Tue, 16 Nov 1999 07:23:02 +0100 Message-ID: <23589.942733382@critter.freebsd.dk> From: Poul-Henning Kamp Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <199911152335.SAA31130@misha.cisco.com>, Mikhail Teterin writes: >Why does not the function in subject use mmap? In my tests, using mmap >instead of reading the file block at a time gave 17-26% performance >improvement: > > The new method: 135735 microseconds per iteration > The old method: 164525 microseconds per iteration > > The new method: 387283 microseconds per iteration > The old method: 529743 microseconds per iteration > >Should I submit patches, or is there a good reason? Thanks! How would it work for a 5GB file ? -- Poul-Henning Kamp FreeBSD coreteam member phk@FreeBSD.ORG "Real hackers run -current on their laptop." FreeBSD -- It will take a long time before progress goes too far! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message