From owner-freebsd-hackers Mon Jun 8 05:34:33 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id FAA03032 for freebsd-hackers-outgoing; Mon, 8 Jun 1998 05:34:33 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from ns1.yes.no (ns1.yes.no [195.119.24.10]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id FAA03010 for ; Mon, 8 Jun 1998 05:34:21 -0700 (PDT) (envelope-from eivind@bitbox.follo.net) Received: from bitbox.follo.net (bitbox.follo.net [195.204.143.218]) by ns1.yes.no (8.8.7/8.8.7) with ESMTP id MAA14158; Mon, 8 Jun 1998 12:34:18 GMT Received: (from eivind@localhost) by bitbox.follo.net (8.8.8/8.8.6) id OAA06819; Mon, 8 Jun 1998 14:33:47 +0200 (MET DST) Message-ID: <19980608143347.59513@follo.net> Date: Mon, 8 Jun 1998 14:33:47 +0200 From: Eivind Eklund To: "Edward P. Katz" Cc: hackers@FreeBSD.ORG Subject: Re: Newbie 3 questions. References: <199806080349.UAA29145@grebe.Stanford.EDU> <199806080414.XAA01195@dyson.iquest.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.89.1i In-Reply-To: <199806080414.XAA01195@dyson.iquest.net>; from John S. Dyson on Sun, Jun 07, 1998 at 11:14:29PM -0500 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Sun, Jun 07, 1998 at 11:14:29PM -0500, John S. Dyson wrote: > The biggest minus (performance wise) that you'll likely notice > about FreeBSD is that we have more synchronous metadata update > policy on our filesystems. This can have a performance impact > for massive filesystem manipulations. FreeBSD consiously chooses > the conservative policy though. ... and (as John well knows) it can be tuned to run an async policy similar to the one in Linux. Which policy you run is a tradeoff between the security of synchronous metadata updates (you get the guarantees that you don't get data crossing over from file to file during crashes, that directories don't get totally screwed up, etc) vs speed in massive manipulation of the filesystem (large amounts of renames, creation of lots of small files, etc). The default policy is the safest of these. Eivind. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message