From owner-freebsd-hackers Fri May 25 10:10:59 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from silby.com (cb34181-a.mdsn1.wi.home.com [24.14.173.39]) by hub.freebsd.org (Postfix) with ESMTP id AFACE37B423 for ; Fri, 25 May 2001 10:10:53 -0700 (PDT) (envelope-from silby@silby.com) Received: (qmail 59011 invoked by uid 1000); 25 May 2001 17:10:49 -0000 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 25 May 2001 17:10:49 -0000 Date: Fri, 25 May 2001 12:10:49 -0500 (CDT) From: Mike Silbersack To: Doug Barton Cc: Ed Hudson , Subject: Re: general speed differences between 4.1.1-RELEASE and 4.3-RELEASE In-Reply-To: <3B0DF980.EDA844F7@DougBarton.net> Message-ID: <20010525120231.L58983-100000@achilles.silby.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, 24 May 2001, Doug Barton wrote: > The current mood (which I agree with) is to make softupdates the default > after installation. The problem with the combo of write caching and > softupdates is that if the power actually goes off the meta-data writes > that softupdates postpones and are further postponed by the write cache > will never happen, therefore leaving the file system in a potentially > unrecoverable state. That mood is nice in theory, but doesn't seem to fit practice. My boxes are on UPSes, and I have trouble remembering the last time the power went out. On the other hand, I can clearly remember the last panic on my -current box which required a manual fsck to repair (yesterday). And yes, write caching was disabled on the box at the time. It seems to me that we're assuming hardware write caching is some evil villan which will steal our data without any evidence. At the same time, we're putting blind trust in filesystems to always DTRT. And stuck in the middle is a growing number of people who are seeing a noticeable slowdown with 4.3, and will start telling their friends that FreeBSD is slow. Mike "Silby" Silbersack To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message