From owner-freebsd-stable Wed Sep 5 1:26: 8 2001 Delivered-To: freebsd-stable@freebsd.org Received: from pc1-stme2-0-cust102.cdf.cable.ntl.com (pc1-stme2-0-cust102.cdf.cable.ntl.com [62.252.56.102]) by hub.freebsd.org (Postfix) with ESMTP id C0E7337B40D; Wed, 5 Sep 2001 01:25:58 -0700 (PDT) Received: from lfarr (snorlax.bka.epcdirect.co.uk [192.168.10.200]) by pc1-stme2-0-cust102.cdf.cable.ntl.com (8.11.3/8.11.3) with ESMTP id f858Pmn44751; Wed, 5 Sep 2001 09:25:48 +0100 (BST) (envelope-from l.farr@epcdirect.co.uk) From: "Lawrence Farr" To: "'Greg Lehey'" , "'Lawrence Farr'" Cc: "'David Gilbert'" , "'Chris BeHanna'" , "'FreeBSD-Stable'" Subject: RE: [stable] Re: RAID5 Date: Wed, 5 Sep 2001 09:26:07 +0100 Message-ID: <002c01c135e4$69c924d0$c80aa8c0@lfarr> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.2627 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2462.0000 Importance: Normal In-Reply-To: <20010905085301.K85816@wantadilla.lemis.com> Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG I did these tests in response to a recent thread on hardware (look for "3ware stuff not ready for heavy duty useage"). I had the hardware ready to build when the whole thing came up, and offered to thrash it in an effort to break it. OK, what I did was write a small shell script that took a 1Mb dump of /dev/urandom And wrote it to disk till it made a ~1Gb file. Then divided seconds elapsed by filesize To get a rough average of speed. Then read the file and averaged the read speed. I did this Until I had filled the partition (140 passes), then did the whole thing again for a day or so. >-----Original Message----- >From: Greg Lehey [mailto:grog@FreeBSD.org] >Sent: 05 September 2001 00:23 >To: Lawrence Farr >Cc: David Gilbert; Chris BeHanna; FreeBSD-Stable >Subject: Re: [stable] Re: RAID5 > > >On Tuesday, 4 September 2001 at 13:52:02 +0100, Lawrence Farr wrote: >> Just to add another benchmark, I got: >> >> Pass 23 - 1048576 kb written in 115 seconds, at 9118 kb/Sec >> Pass 23 - 1048576 kb read in 15 seconds, at 69905 kb/Sec > >This shows there's a big difference. Which is which? What is it >really doing here? > >Greg >-- >See complete headers for address and phone numbers > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message