From owner-freebsd-current Fri Apr 5 11:15:43 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id LAA03395 for current-outgoing; Fri, 5 Apr 1996 11:15:43 -0800 (PST) Received: from mramirez.sy.yale.edu (mramirez.sy.yale.edu [130.132.57.207]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id LAA03387 for ; Fri, 5 Apr 1996 11:15:29 -0800 (PST) Received: (from mrami@localhost) by mramirez.sy.yale.edu (8.6.12/8.6.9) id OAA06266; Fri, 5 Apr 1996 14:13:11 -0500 Date: Fri, 5 Apr 1996 14:13:11 -0500 (EST) From: Marc Ramirez Reply-To: mrami@minerva.cis.yale.edu To: Satoshi Asami cc: current@freebsd.org, nisha@cs.berkeley.edu, tege@matematik.su.se, hasty@rah.star-gate.com Subject: Re: fast memory copy for large data sizes In-Reply-To: <199604050935.BAA24263@silvia.HIP.Berkeley.EDU> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk On Fri, 5 Apr 1996, Satoshi Asami wrote: > We've put together a fast memory copy that uses floating point > registers to speed up large transfers. The original idea was taken > from Amancio Hasty's old post to use floating point registers to move > 8 bytes at a time. (We tried using integer registers too but with our > wits we could only get 10MB/s less than the FP case.) P5's and up only, please. :) AMD 486/66: mrami[~/bcopy]$ make >> running tests sh runtests size libc ours 32 7.629395 MB/s 7.629395 MB/s 64 12.207031 MB/s 4.695012 MB/s 128 12.207031 MB/s 3.487723 MB/s 256 12.207031 MB/s 6.424753 MB/s 512 12.520032 MB/s 7.076540 MB/s 1024 12.682630 MB/s 7.454676 MB/s 2048 12.682630 MB/s 7.570252 MB/s 4096 10.146104 MB/s 7.629395 MB/s 8192 12.682630 MB/s 7.666830 MB/s 16384 12.703252 MB/s 7.689469 MB/s 32768 12.682630 MB/s 7.517440 MB/s 65536 12.183236 MB/s 7.472501 MB/s 131072 12.090144 MB/s 7.526040 MB/s 262144 12.569762 MB/s 7.717717 MB/s 524288 12.419583 MB/s 7.534773 MB/s 1048576 11.838803 MB/s 7.718551 MB/s 2097152 12.164192 MB/s 7.725020 MB/s 4194304 12.290410 MB/s 7.719504 MB/s mrami[~/bcopy]$ Marc. -- Every four seconds a woman has a baby. Our problem is to find this woman and stop her.