From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Majed B." Subject: Re: Raid 5 Read performance Date: Fri, 11 Sep 2009 21:22:31 +0300 Message-ID: <70ed7c3e0909111122n6b78a45asc92cd0b84d70f07a@mail.gmail.com> References: <70ed7c3e0909101317l3298743co414a2626c765d00c@mail.gmail.com> <918883.43112.qm@web94815.mail.in2.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <918883.43112.qm@web94815.mail.in2.yahoo.com> Sender: linux-raid-owner@vger.kernel.org To: satha kottidi Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids All kernel changes are mentioned in the changelogs, so I think you can find what you want at kernel.org -- it also mentions who did the change, so you can contact him/her directly. I'm not saying you won't find help here, but the aforementioned is a better chance :) On Fri, Sep 11, 2009 at 6:48 PM, satha kottidi = wrote: > Hi Majed & All, > > Yes we two are working together. Actually we found a change in md/rai= d5.c > file in the function sync_request() it restricts the numbers, the ker= nel > 2.6.27 has code like this > > while(unlikely(!handle_stripe(sh, NULL))) > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0 ; > =C2=A0But in kernel 2.6.21 it simply the handle_stripe(sh, NULL) call= =2E > > Can anybody tell me the necessity of the change, and why it reduces t= he > numbers. Any comments is very helpful for me to analyze the driver fu= rther. > > > Thanks, > Satha. > > --- On Fri, 11/9/09, Majed B. wrote: > > From: Majed B. > Subject: Re: Raid 5 Read performance > To: "Koti" > Cc: linux-raid@vger.kernel.org > Date: Friday, 11 September, 2009, 1:47 AM > > Someone else has already emailed the mailing list about this. Are you > two running an assignment or something?! > > Check the mailing list archive for whatever people have already repli= ed > with. > > On Thu, Sep 10, 2009 at 11:07 PM, Koti wrote: >> Hi All >> >> I am trying measure the RAID 5 Read numbers on linux kernel-2.6.21 a= nd >> kernel 2.6.27 the numbers are lower on later kernel (2.6.27). Iam >> measuring >> the numbers using "time dd" command (4GB ). Is any valid reason for = this, >> or >> Am missing anything in the process. Can anybody help me in analyze t= his >> problem. >> >> Thanks, >> Koti >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-raid= " in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > > > -- > =C2=A0 =C2=A0 =C2=A0=C2=A0=C2=A0Majed B. > > ________________________________ > Connect more, do more and share more with Yahoo! India Mail. Learn mo= re. --=20 Majed B. -- 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