From owner-freebsd-questions Sat Aug 16 08:27:24 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id IAA27471 for questions-outgoing; Sat, 16 Aug 1997 08:27:24 -0700 (PDT) Received: from smtp1.xs4all.nl (smtp1.xs4all.nl [194.109.6.51]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id IAA27466 for ; Sat, 16 Aug 1997 08:27:18 -0700 (PDT) Received: from asterix.xs4all.nl (root@asterix.xs4all.nl [194.109.6.11]) by smtp1.xs4all.nl (8.8.6/XS4ALL) with ESMTP id RAA16825; Sat, 16 Aug 1997 17:27:12 +0200 (MET DST) Received: from plm.xs4all.nl (uucp@localhost) by asterix.xs4all.nl (8.8.6/8.8.6) with UUCP id RAA26588; Sat, 16 Aug 1997 17:25:57 +0200 (MET DST) Received: (from plm@localhost) by plm.xs4all.nl (8.8.6/8.7.3) id RAA08121; Sat, 16 Aug 1997 17:21:51 +0200 (MET DST) To: Paul Dekkers Cc: freebsd-questions@freebsd.org Subject: Re: FreeBSD is slower than Linux !? References: <87203vbbo3.fsf@totally-fudged-out-message-id> From: Peter Mutsaers Date: 16 Aug 1997 17:21:49 +0200 In-Reply-To: Paul Dekkers's message of Thu, 14 Aug 1997 22:23:19 +0200 (MET DST) Message-ID: <87g1sa9mr6.fsf@plm.xs4all.nl> Lines: 62 X-Mailer: Gnus v5.4.25/Emacs 19.34 Sender: owner-freebsd-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk >> On Thu, 14 Aug 1997 22:23:19 +0200 (MET DST), Paul Dekkers >> said: PD> On Wed, 13 Aug 1997, Shawn Ramsey wrote: >> Do be fair, I think you should mount the FreeBSd disks asyncronously. By >> default, it is set to Synchronously. Linux, at least it used to be this >> way, is mounted asynch. Disk access is HUGELY increases under FreeBSD if >> it is set to asynch. (mount -o async /dev/filesystem) PD> Joking? Look at my dd-test: PD> Linux fBSD fBSD with async (linux with sync) PD> dd-test 2.61 4.95 4.78 2m06 (!!) PD> also with the other tests fBSD is still slower and the sync is faster, PD> even faster than last time without async, so FreeBSD really wrote PD> everything already. PD> and I'm sure the / was mounted with async! (checked with mount) PD> i'm using an i486 with 40mb's of memory so that should be enough for PD> FreeBSD to do something :-) Hmm, you must be doing something wrong. I run Linux (debian 1.3.1 and current) and FreeBSD (current) on the same machine. They both have a partition on the same disk. Since I'm kind of a benchmark fanatic I've been testing and comparing them quite a lot. I like Linux for it's nice appls (netscape plugins, dosemu etc), but for sure FreeBSD's performance beats Linux on almost all points. I test both on my machine which is a P90 with 48MB and SCSI disks (NCR815 controller). Of course, performance for Linux and FreeBSD may differ when using different types of hardware (e.g. IDE iso SCSI, or different types of IDE) or different versions. Maybe in your special case indeed Linux is faster in the dd test, but usually it is not. Did you: - recompile both kernels with same level of gcc and optimization options? - test both using the same disk, and also using a partition that is about on the same spot of the disk (the start of a disk can be quite a bit faster as the end of it). - Use options for dd to make sure that the same blocksizes were used? - etc. etc. Generally: dd on a disk is faster in FreeBSD. Also is NFS (read and write), and things like doing an 'ls directory' on a directory that contains lots (thousands) of files. Paging and multitasking behaviour, and filesystem cache are also much nicer and faster on FreeBSD. When I switch to Linux I'm always annoyed by its (relative) slowness and esp. bad multitasking (paging and fs. caching ) behaviour: one process like a tape read can eat up all of the filesystem cache and make the system real slow. -- /\_/\ ( o.o ) Peter Mutsaers | Abcoude (Utrecht), | Trust me, I know ) ^ ( plm@xs4all.nl | the Netherlands | what I'm doing.