From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Ryan Earl" Subject: RE: RAID1 & 2.6.9 performance problem Date: Tue, 18 Jan 2005 13:18:47 -0600 Message-ID: References: <1106073663.14134.249.camel@pipi.ma.cx> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1106073663.14134.249.camel@pipi.ma.cx> Sender: linux-raid-owner@vger.kernel.org To: Janusz Zamecki Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids I missed that, sounds like you got an IDE concurrency problem. Perhaps= you can't read from both ports for some reason. Don't think it's a raid pr= oblem though. -ryan -----Original Message----- =46rom: Janusz Zamecki [mailto:janusz@pipi.ma.cx] Sent: Tuesday, January 18, 2005 12:41 PM To: J. Ryan Earl Cc: linux-raid@vger.kernel.org Subject: RE: RAID1 & 2.6.9 performance problem W li=B6cie z wto, 18-01-2005, godz. 18:34, J. Ryan Earl pisze: > "You will get 2 parallel sequential reads at around 120MB/sec > assuming you're not bus limited." > > To clarify because this looks ambiguous to me now, you should be able= to > perform 2 parallel sequential reads both at 60MB/sec =3D 120MB/sec to= tal. > > -ryan > Hi, Unfortunatelly it is not the case. Please go to my original e-mail. I'v= e ran two simultaneous tests and I get: hdparm -t /dev/md6 & hdparm -t /dev/md6 This is the result: --disk/hdg----disk/hde- _read write _read write 0 0 : 0 0 0 0 : 0 0 124k 0 :26.0M 0 368k 0 :45.5M 0 0 0 : 0 0 0 0 : 896k 0 124k 0 :1568k 0 0 0 : 0 0 One disk works with 75% of its full speed, the second one works with 0,6% of its full speed or even less. Best regards, Janusz - To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html