From owner-freebsd-chat Sun Jun 17 9:34:16 2001 Delivered-To: freebsd-chat@freebsd.org Received: from mb1i0.ns.pitt.edu (mb1i0.ns.pitt.edu [136.142.186.35]) by hub.freebsd.org (Postfix) with ESMTP id 55B8E37B405 for ; Sun, 17 Jun 2001 09:34:12 -0700 (PDT) (envelope-from pfg1+@pitt.edu) Received: from pitt.edu ("port 1032"@[136.142.23.42]) by pitt.edu (PMDF V5.2-32 #41462) with ESMTP id <01K4VGK5IVF0001O8P@mb1i0.ns.pitt.edu> for freebsd-chat@FreeBSD.ORG; Sun, 17 Jun 2001 12:34:11 EST Date: Sun, 17 Jun 2001 12:40:56 -0400 From: "Pedro F. Giffuni" Subject: Re: Article Network performance by OS To: freebsd-chat@FreeBSD.ORG Cc: Dag-Erling Smorgrav Message-id: <3B2CDD98.95548872@pitt.edu> Organization: University of Pittsburgh MIME-version: 1.0 X-Mailer: Mozilla 4.76 [en] (Win98; U) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Accept-Language: en,pdf,es-CO References: Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Dag-Erling Smorgrav wrote: > > Rik van Riel writes: > > Not quite. Linux distributions tend to be extremely > > conservative in the IDE options (DMA, interrupt unmasking, > > write caching, etc. all disabled) while FreeBSD seems to > > have write caching and DMA on by default... > > Ahem. > > First of all, Linux' file system (ext2fs) is more or less equivalent, > in terms of performance and integrity, to async ffs. This gives Linux > a big performance edge out of the box, and FreeBSD a big reliability > edge - but benchmark authors rarely care about fs integrity, as > shutting off the power during heavy disk I/O isn't generally part of > their benchmark. > This procedure would provide an excellent test of reliability. I think, however, that it's easier to find and maintain an UPS instead of hiring a FreeBSD expert. OK...tunning is not rocket science, but if your want reliable operation you really need an UPS anyways, and FreeBSD admins are not easily found (wrt to lusers and wusers). > Second, we tried turning write caching on ATA drives off by default, > and boy were you (the user community) pissed. Yes, turning wc off > shows you just how crappy those non-tagged-queueing 4000 RPM ATA > drives you picked up at Fry's for some pocket change are. So we > turned it back on. If you're not happy with that, put 'hw.ata.wc="0"' > in your /boot/loader.conf and they'll be off after the next reboot. > Or get real disks. > Whatever the technical merits of turning wc off, I think it was a huge mistake; especially since softupdates were not enabled by default. People who (like me) buy those cheap, low quality, drives, are actually expecting this "crappy" behaviour, but really appreciate having a little more performance. cheers, Pedro. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message