From owner-freebsd-questions Fri Aug 15 03:29:46 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id DAA20045 for questions-outgoing; Fri, 15 Aug 1997 03:29:46 -0700 (PDT) Received: from implode.root.com (implode.root.com [198.145.90.17]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id DAA20039 for ; Fri, 15 Aug 1997 03:29:43 -0700 (PDT) Received: from implode.root.com (localhost [127.0.0.1]) by implode.root.com (8.8.5/8.8.5) with ESMTP id DAA14879; Fri, 15 Aug 1997 03:31:23 -0700 (PDT) Message-Id: <199708151031.DAA14879@implode.root.com> To: Paul Dekkers cc: "Jay D. Nelson" , Shawn Ramsey , freebsd-questions@FreeBSD.ORG Subject: Re: FreeBSD is slower than Linux !? In-reply-to: Your message of "Thu, 14 Aug 1997 22:20:33 +0200." From: David Greenman Reply-To: dg@root.com Date: Fri, 15 Aug 1997 03:31:23 -0700 Sender: owner-freebsd-questions@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk >>>> > Linux FreeBSD >>>> >dd 2.61 4.95 dd if=/dev/zero of=/test bs=1024 count=5000 The blocksize is critical to this benchmark. Try a larger blocksize: [implode:dg] time dd if=/dev/zero of=/foo bs=1024 count=5000 5000+0 records in 5000+0 records out 5120000 bytes transferred in 2 secs (2560000 bytes/sec) 0.015u 0.915s 0:01.34 68.6% 74+271k 1+86io 3pf+0w [implode:dg] time dd if=/dev/zero of=/foo bs=50k count=100 100+0 records in 100+0 records out 5120000 bytes transferred in 1 secs (5120000 bytes/sec) 0.000u 0.294s 0:00.51 56.8% 97+609k 0+85io 0pf+0w ...a much larger block size is nearly 3 times faster on a machine here. This particular benchmark isn't really all that useful in any case since it is sensitive to many different factors, not the least of which is the speed of /dev/zero, which has not been optimized much in FreeBSD. -DG David Greenman Core-team/Principal Architect, The FreeBSD Project