MESSAGE
| DATE | 2014-12-06 |
| FROM | Maneesh Kongara
|
| SUBJECT | Re: [LIU Comp Sci] Parity Bit Algebra
|
From owner-learn-outgoing-at-mrbrklyn.com Sat Dec 6 22:02:25 2014
Return-Path:
X-Original-To: archive-at-mrbrklyn.com
Delivered-To: archive-at-mrbrklyn.com
Received: by mrbrklyn.com (Postfix)
id AC04C16007B; Sat, 6 Dec 2014 22:02:25 -0500 (EST)
Delivered-To: learn-outgoing-at-mrbrklyn.com
Received: by mrbrklyn.com (Postfix, from userid 28)
id 9510116112F; Sat, 6 Dec 2014 22:02:25 -0500 (EST)
Delivered-To: learn-at-mrbrklyn.com
Received: from mail-qc0-f179.google.com (mail-qc0-f179.google.com [209.85.216.179])
by mrbrklyn.com (Postfix) with ESMTP id A2B1616007B
for ; Sat, 6 Dec 2014 22:02:24 -0500 (EST)
Received: by mail-qc0-f179.google.com with SMTP id c9so2170386qcz.38
for ; Sat, 06 Dec 2014 19:02:24 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20120113;
h=mime-version:in-reply-to:references:date:message-id:subject:from:to
:content-type;
bh=a4eBHr3h7y8fbBbSfnonFLK3euAXJNQ44ORqtAJKh14=;
b=vmd7nOFuY0In15NA3QNImzNB6mcgWfqbdV5tgTIQoj0TmYg1CB3Ln/Qx7Z3yg6Girc
iGrXPlPuvNfUFhb+rdXVlYgRuqw+YchOJKjxc5isRYw1jvlhlXjfXvmkngug9GlcCi98
o24PEG1zsPLNlbAMM316NhrLZKeP22z5fSbu+x40OEfdo7g4OgYkm1rFT5wZVgsUi9dI
SqwYWJBET4Eu9fkFUiVdpDZbllGF5aVdvGHFcxRt/d4UPhDlGh3Cwi5276+VZH5xsEGx
KtLtdQByq328xWShk7dMv23qLmHL/NzZu4H6k41lyEloRh5IXWI1RVTU3wvb7jMZdAFh
wbXg==
MIME-Version: 1.0
X-Received: by 10.224.22.6 with SMTP id l6mr40606002qab.31.1417921344319; Sat,
06 Dec 2014 19:02:24 -0800 (PST)
Received: by 10.141.1.136 with HTTP; Sat, 6 Dec 2014 19:02:24 -0800 (PST)
Received: by 10.141.1.136 with HTTP; Sat, 6 Dec 2014 19:02:24 -0800 (PST)
In-Reply-To:
References: <54838832.6010205-at-panix.com>
<54838C85.60705-at-panix.com>
<5483BD3C.9020609-at-panix.com>
<5483C042.2050104-at-panix.com>
<5483C287.3030707-at-panix.com>
Date: Sat, 6 Dec 2014 22:02:24 -0500
Message-ID:
Subject: Re: [LIU Comp Sci] Parity Bit Algebra
From: Maneesh Kongara
To: learn-at-mrbrklyn.com
Content-Type: multipart/alternative; boundary=047d7bf0d4ae0c35840509978aa1
Sender: owner-learn-at-mrbrklyn.com
Precedence: bulk
Reply-To: learn-at-mrbrklyn.com
--047d7bf0d4ae0c35840509978aa1
Content-Type: text/plain; charset=UTF-8
Damn! I get it now!!!
On Dec 6, 2014 10:00 PM, "Maneesh Kongara" wrote:
> It gives us the desired answer?
> On Dec 6, 2014 9:58 PM, "Ruben Safir" wrote:
>
>> On 12/07/2014 02:50 AM, Maneesh Kongara wrote:
>> > Have you seen the review questions?
>>
>>
>> What happens when you subtract a comp 2 number again and again
>>
>>
>> >
>> > On Sat, Dec 6, 2014, 9:49 PM Ruben Safir wrote:
>> >
>> >>
>> >> I can't even read the question
>> >>
>> >>
>> >>
>> >> On 12/07/2014 02:38 AM, Maneesh Kongara wrote:
>> >>> I've finished all other questions... I'm breaking my head with the
>> last
>> >>> question.
>> >>> On Dec 6, 2014 9:36 PM, "Ruben Safir" wrote:
>> >>>
>> >>>> On 12/06/2014 11:09 PM, Maneesh Kongara wrote:
>> >>>>> Preliminary work as in answers to the other questions of the
>> >> assignment?
>> >>>>> On Dec 6, 2014 6:08 PM, "Ruben Safir" wrote:
>> >>>> I'm going to crash, how far did you get in the assingment.
>> >>>>
>> >>>> Call me is 20 minutes. I have one hour to do it :)
>> >>>>
>> >>>>
>> >>>>>> On 12/06/2014 10:52 PM, Maneesh Kongara wrote:
>> >>>>>>> Thanks so much for sharing Mr Rubin. Have you completed the
>> >> assignment?
>> >>>>>>> On Dec 6, 2014 5:49 PM, "Ruben Safir" wrote:
>> >>>>>> Not even looked at it outside of the library. I'm burning up
>> trying
>> >> to
>> >>>>>> catch up. Do you have some preliminary work?
>> >>>>>>
>> >>>>>> I did give it throught. Part of the solution must have to do with
>> the
>> >>>>>> Comp + 2 binary
>> >>>>>>
>> >>>>>> I can't even find my notes...
>> >>>>>>
>> >>>>>>>> This is from theidiscussion of Raid 3 Stallings Text which the
>> slide
>> >>>>>>>> come from. It is related to the problem you asked about the
>> parity
>> >>>> bit
>> >>>>>>>> calculation for the Hamming Code
>> >>>>>>>>
>> >>>>>>>> Not the methodology for logical calculation, it is straight math
>> >>>>>>>>
>> >>>>>>>> Note that X is XOR for whatever UFT reason
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> REDUNDANCY In the event of a drive failure, the parity drive is
>> >>>> accessed
>> >>>>>>>> and data is reconstructed from the remaining devices. Once the
>> >> failed
>> >>>>>>>> drive is replaced, the missing data can be restored on the new
>> drive
>> >>>> and
>> >>>>>>>> operation resumed.
>> >>>>>>>>
>> >>>>>>>> Data reconstruction is simple. Consider an array of five drives
>> in
>> >>>> which
>> >>>>>>>> X0 through X3 contain data and X4 is the parity disk.The parity
>> for
>> >>>> the
>> >>>>>>>> ith bit is calculated as follows:
>> >>>>>>>>
>> >>>>>>>> X4(i) = X3(i) { X2(i) { X1(i) { X0(i)
>> >>>>>>>>
>> >>>>>>>> where { is exclusive-OR function.
>> >>>>>>>>
>> >>>>>>>> Suppose that drive X1 has failed. If we add X4(i) { X1(i) to both
>> >>>> sides
>> >>>>>>>> of the preceding equation, we get
>> >>>>>>>>
>> >>>>>>>> X1(i) = X4(i) { X3(i) { X2(i) { X0(i)
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> file:///home/ruben/william stallings - computer organization and
>> >>>>>>>> architecture designing for performance (8th edition).pdf
>> >>>>>>>>
>> >>>>>>>> Page 202
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> http://www.nylxs.com/images/raid3_parity_math.png
>> >>>>>>>>
>> >>>>>>>> Ruben
>> >>>>>>>>
>> >>
>>
>>
--047d7bf0d4ae0c35840509978aa1
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Damn! I get it now!!!
On Dec 6, 2014 10:00 PM, "Maneesh Kongara&q= uot; < maneeshkongara-at-gmail.c=
om> wrote: style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> dir=3D"ltr">It gives us the desired answer?
On Dec 6, 2014 9:58 PM, "Ruben Safir" = < mrbrklyn-at-panix.=
com> wrote: " style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">O=
n 12/07/2014 02:50 AM, Maneesh Kongara wrote:
> Have you seen the review questions?
What happens when you subtract a comp 2 number again and again
>
> On Sat, Dec 6, 2014, 9:49 PM Ruben Safir <n-at-panix.com" target=3D"_blank">mrbrklyn-at-panix.com> wrote:
>
>>
>> I can't even read the question
>>
>>
>>
>> On 12/07/2014 02:38 AM, Maneesh Kongara wrote:
>>> I've finished all other questions... I'm breaking my h=
ead with the last
>>> question.
>>> On Dec 6, 2014 9:36 PM, "Ruben Safir" <"mailto:mrbrklyn-at-panix.com" target=3D"_blank">mrbrklyn-at-panix.com> wr=
ote:
>>>
>>>> On 12/06/2014 11:09 PM, Maneesh Kongara wrote:
>>>>> Preliminary work as in answers to the other questions =
of the
>> assignment?
>>>>> On Dec 6, 2014 6:08 PM, "Ruben Safir" < href=3D"mailto:mrbrklyn-at-panix.com" target=3D"_blank">mrbrklyn-at-panix.com>> wrote:
>>>> I'm going to crash, how far did you get in the assingm=
ent.
>>>>
>>>> Call me is 20 minutes.=C2=A0 I have one hour to do it :)r>
>>>>
>>>>
>>>>>> On 12/06/2014 10:52 PM, Maneesh Kongara wrote:
>>>>>>> Thanks so much for sharing Mr Rubin. Have you =
completed the
>> assignment?
>>>>>>> On Dec 6, 2014 5:49 PM, "Ruben Safir"=
; <mrbrklyn-at-pani=
x.com> wrote:
>>>>>> Not even looked at it outside of the library.=C2=
=A0 I'm burning up trying
>> to
>>>>>> catch up.=C2=A0 Do you have some preliminary work?=
>>>>>>
>>>>>> I did give it throught.=C2=A0 Part of the solution=
must have to do with the
>>>>>> Comp + 2 binary
>>>>>>
>>>>>> I can't even find my notes...
>>>>>>
>>>>>>>> This is from theidiscussion of Raid 3 Stal=
lings Text which the slide
>>>>>>>> come from.=C2=A0 It is related to the prob=
lem you asked about the parity
>>>> bit
>>>>>>>> calculation for the Hamming Code
>>>>>>>>
>>>>>>>> Not the methodology for logical calculatio=
n, it is straight math
>>>>>>>>
>>>>>>>> Note that X is XOR for whatever UFT reason=
>>>>>>>>
>>>>>>>>
>>>>>>>> REDUNDANCY In the event of a drive failure=
, the parity drive is
>>>> accessed
>>>>>>>> and data is reconstructed from the remaini=
ng devices. Once the
>> failed
>>>>>>>> drive is replaced, the missing data can be=
restored on the new drive
>>>> and
>>>>>>>> operation resumed.
>>>>>>>>
>>>>>>>> Data reconstruction is simple. Consider an=
array of five drives in
>>>> which
>>>>>>>> X0 through X3 contain data and X4 is the p=
arity disk.The parity for
>>>> the
>>>>>>>> ith bit is calculated as follows:
>>>>>>>>
>>>>>>>> X4(i) =3D X3(i) { X2(i) { X1(i) { X0(i)>
>>>>>>>>
>>>>>>>> where { is exclusive-OR function.
>>>>>>>>
>>>>>>>> Suppose that drive X1 has failed. If we ad=
d X4(i) { X1(i) to both
>>>> sides
>>>>>>>> of the preceding equation, we get
>>>>>>>>
>>>>>>>> X1(i) =3D X4(i) { X3(i) { X2(i) { X0(i)>
>>>>>>>>
>>>>>>>>
>>>>>>>> file:///home/ruben/william stallings - com=
puter organization and
>>>>>>>> architecture designing for performance (8t=
h edition).pdf
>>>>>>>>
>>>>>>>> Page 202
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> d3_parity_math.png" target=3D"_blank">http://www.nylxs.com/images/raid3_par=
ity_math.png
>>>>>>>>
>>>>>>>> Ruben
>>>>>>>>
>>
--047d7bf0d4ae0c35840509978aa1--
|
|
