From owner-freebsd-scsi Sat Mar 23 10:54:33 2002 Delivered-To: freebsd-scsi@freebsd.org Received: from web20503.mail.yahoo.com (web20503.mail.yahoo.com [216.136.226.138]) by hub.freebsd.org (Postfix) with SMTP id 2568137B400 for ; Sat, 23 Mar 2002 10:54:31 -0800 (PST) Message-ID: <20020323185430.80848.qmail@web20503.mail.yahoo.com> Received: from [66.81.25.59] by web20503.mail.yahoo.com via HTTP; Sat, 23 Mar 2002 10:54:30 PST Date: Sat, 23 Mar 2002 10:54:30 -0800 (PST) From: F J Subject: SCSI write semantics To: freebsd-scsi@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Are the SCSI disk writes atomic or they're hardware dependent? What I mean is that if you issue a 32KB write and the power goes off at the same time, is there any gauarantee that either the disk blocks will be updated completely or nothing will be written at all? what about SCSI RAID controllers? Another concern is that DMA may be in progress while memory contents become unstable. Is this possible? Regards, fj __________________________________________________ Do You Yahoo!? Yahoo! Movies - coverage of the 74th Academy Awards® http://movies.yahoo.com/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message