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Subject: RE: func spec for online eek
Date: Fri, 3 Aug 2007 13:58:47 -0700
Message-ID: <BB375AF679D4A34E9CA8DFA650E2B04E02BEF082@onstor-exch02.onstor.net>
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Thread-Topic: func spec for online eek
Thread-Index: AcfObIzcE3Q/jvgWS2+WAMAdkq8T3QBMUSEhAAEKkdAAAZ2IIAADslwAAMNTxXAAzmqtsAAEom6Q
From: "Henry Lau" <henry.lau@onstor.com>
To: "Maxim Kozlovsky" <maxim.kozlovsky@onstor.com>,
	"Jonathan Goldick" <jonathan.goldick@onstor.com>,
	"Jobi Ariyamannil" <jobi.ariyamannil@onstor.com>,
	"dl-Design Review" <dl-designreview@onstor.com>

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I am working on using non-contiguous memory for eek to setup the bitmap
if contiguous memory is not available.

=20

Henry

=20

________________________________

From: Maxim Kozlovsky=20
Sent: Friday, August 03, 2007 1:35 PM
To: Jonathan Goldick; Jobi Ariyamannil; dl-Design Review
Subject: RE: func spec for online eek

=20

The last number for the largest customer volume I heard was 30Tb,
30*16=3D480 which is too much even for 2480. Having enough memory is =
just
a part of the problem, another part is getting the contiguous memory as
the current eek requires.

=20

________________________________

From: Jonathan Goldick=20
Sent: Monday, July 30, 2007 9:31 AM
To: Jobi Ariyamannil; Sandrine Boulanger; Raj Kumar; dl-Design Review
Subject: RE: func spec for online eek

=20

We need to characterize the performance impacts.  The IO load probably
is not important but 1 bit/8KB block --> 16MB mem/1TB disk.  This amount
of memory can be risky given the file system's penchant for crashing on
a memory outage.  To test this we need to have a large file system in
terms of blocks and generate a load that is memory intensive, like many
dumps, mirrors, etc.  We can use EMRS to find the largest customer file
system to date, and then create a larger one to assume typical growth.

=20

=20

________________________________

From: Jobi Ariyamannil=20
Sent: Thursday, July 26, 2007 12:15 PM
To: Sandrine Boulanger; Raj Kumar; dl-Design Review
Subject: RE: func spec for online eek

=20

See my comments inline.

=20

________________________________

From: Sandrine Boulanger=20
Sent: Thursday, July 26, 2007 10:33 AM
To: Jobi Ariyamannil; Raj Kumar; dl-Design Review
Subject: RE: func spec for online eek

=20

Comments/Questions:

=20

5: about new option to turn on/off online eek =3D> I though we already
reached the max of options for the volume CLI cmds? I think if we use
them all in the same volume create they don't fit for nfxsh...

JOBI>  I did not know that and I cannot address this issue as part of
online eek.  Also understand that initially online eek will be enabled
using "vol modify" when we suspect filesystems are running into
corruption issues, I don't recommend turning it on all filesystems in
production by default.  A lot of times, customers ask for some sort
online recovery feature and in those situations we can turn on this
feature by itself using "vol modify" command.

5.1: is the order in which volumes are "online eeked" random?

JOBI> Yes.

5.1: "The background activity should be suspended [...] under extreme
load" =3D> how is the load evaluated?

JOBI>  I plan to look at the load in various caches.

5.2: "FS is flagged as online eek in progress" =3D> is it something that
can be verified? With fsdb?

JOBI>  This is an incore state and something internal.

5.2: "If modifications are done to inodes already processed by eek
thred, those transactions will update the eek bitmap while freeing or
allocating blocks" =3D> Unit test, hooks to validate?

JOBI> Generating traffic while online eek is in progress, will test the
scenerio.  I can add elog messages when online eek starts and stops.

6: "ONLINE-REPAIR is number of weeks" =3D> in intro for 5, unit =
mentioned
is days

JOBI> It should be weeks, I will fix that.

9: We can add (not exhaustive list):

- Modification of inodes already checked by eek thread

- Vsvr move, snap revert, mirror, backup/restore... when online eek is
running

- Online eek when system is under load (at what point is the thread
stopped)

- Performance

JOBI> ok

=20

=20

________________________________

From: Jobi Ariyamannil=20
Sent: Thursday, July 26, 2007 9:41 AM
To: Raj Kumar; dl-Design Review
Subject: RE: func spec for online eek

=20

Thanks again, Raj. See my comments below.

=20

1.	We have some code in place to take care of this situation
(setting the filesystem version correctly after revert) already, but
that is not fool proof.  Since we may make more layout changes in
future, I thought to fix this issue correctly.  So no issues with older
snapshots, they will work.
2.	If the target does not understand the layout version of the
source filesystem, remote mirroring will fail and they need to upgrade
the software on the target to a release which understands the layout.
Since some of the filesystem hardening work are specific to certain
layouts, certain times we need to force that.  I am not sure how
frequently we encounter the situation of source and target running
different releases in the field.  Let me think and discuss this issue
some more.

=20

Regards,

Jobi

=20

=20

________________________________

From: Raj Kumar=20
Sent: Thursday, July 26, 2007 8:59 AM
To: Jobi Ariyamannil; dl-Design Review
Subject: RE: func spec for online eek

=20

Looks good. Few comments:

=20

* Section 5.5:  Track version while taking snapshot: Can we still
support reverting to older snapshots since they wont have version
information?

* This change will force the DMIP customers to upgrade their target DMIP
cluster to Zonda. Currently they don't need to it. No big deal but need
to make sure support is aware of this.

=20

________________________________

From: Jobi Ariyamannil
Sent: Tue 7/24/2007 8:33 PM
To: dl-Design Review
Subject: func spec for online eek

Hi,

=20

Please review the attached func spec for online eek feature planned for
zonda.

We plan to deliver the framework and online detection/repair of
duplicate blocks and incorrect refcounts (live bit).

Please let me know any comments you may have.

=20

Regards,

Jobi


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<body lang=3DEN-US link=3Dblue vlink=3Dpurple>

<div class=3DSection1>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>I am working on using =
non-contiguous memory
for eek to setup the bitmap if contiguous memory is not =
available.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Henry<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> Maxim =
Kozlovsky <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Friday, August 03, =
2007 1:35
PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> Jonathan Goldick; =
Jobi
Ariyamannil; dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>The last number for the largest =
customer
volume I heard was 30Tb, 30*16=3D480 which is too much even for 2480. =
Having
enough memory is just a part of the problem, another part is getting the
contiguous memory as the current eek =
requires.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div style=3D'border:none;border-left:solid blue 1.5pt;padding:0in 0in =
0in 4.0pt'>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> =
Jonathan Goldick
<br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Monday, July 30, =
2007 9:31
AM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Jobi
 Ariyamannil</st1:PersonName>; <st1:PersonName w:st=3D"on">Sandrine =
Boulanger</st1:PersonName>;
Raj Kumar; dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>We need to characterize the =
performance
impacts. &nbsp;The IO load probably is not important but 1 bit/8KB block =
</span></font><font
size=3D2 color=3Dnavy face=3DWingdings><span =
style=3D'font-size:10.0pt;font-family:
Wingdings;color:navy'>&agrave;</span></font><font size=3D2 color=3Dnavy =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial;color:navy'> 16MB mem/1TB =
disk.
&nbsp;This amount of memory can be risky given the file system&#8217;s =
penchant
for crashing on a memory outage. &nbsp;To test this we need to have a =
large
file system in terms of blocks and generate a load that is memory =
intensive,
like many dumps, mirrors, etc.&nbsp; We can use EMRS to find the largest
customer file system to date, and then create a larger one to assume =
typical
growth.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> =
<st1:PersonName
w:st=3D"on">Jobi Ariyamannil</st1:PersonName> <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Thursday, July 26, =
2007
12:15 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Sandrine
 Boulanger</st1:PersonName>; Raj Kumar; dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>See my comments =
inline.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> =
<st1:PersonName
w:st=3D"on">Sandrine Boulanger</st1:PersonName> <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Thursday, July 26, =
2007
10:33 AM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Jobi
 Ariyamannil</st1:PersonName>; Raj Kumar; dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Comments/Questions:<o:p></o:p></span=
></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>5: about new option to turn on/off =
online
eek =3D&gt; I though we already reached the max of options for the =
volume CLI
cmds? I think if we use them all in the same volume create they =
don&#8217;t fit
for nfxsh&#8230;<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt;&nbsp; I did not know that =
and I
cannot address this issue as part of online eek.&nbsp; Also understand =
that
initially online eek will be enabled using &#8220;vol modify&#8221; when =
we
suspect filesystems are running into corruption issues, I don&#8217;t =
recommend
turning it on all filesystems in production by default.&nbsp; A lot of =
times,
customers ask for some sort online recovery feature and in those =
situations we
can turn on this feature by itself using &#8220;vol modify&#8221; =
command.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>5.1: is the order in which volumes =
are
&#8220;online eeked&#8221; random?<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt; =
Yes.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>5.1: &#8220;The background activity =
should
be suspended [&#8230;] under extreme load&#8221; =3D&gt; how is the load
evaluated?<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt;&nbsp; I plan to look at the =
load
in various caches.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>5.2: &#8220;FS is flagged as online =
eek in
progress&#8221; =3D&gt; is it something that can be verified? With =
fsdb?<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt;&nbsp; This is an incore =
state and
something internal.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>5.2: &#8220;If modifications are =
done to
inodes already processed by eek thred, those transactions will update =
the eek
bitmap while freeing or allocating blocks&#8221; =3D&gt; Unit test, =
hooks to
validate?<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt; Generating traffic while =
online
eek is in progress, will test the scenerio.&nbsp; I can add elog =
messages when
online eek starts and stops.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>6: &#8220;ONLINE-REPAIR is number =
of <i><span
style=3D'font-style:italic'>weeks</span></i>&#8221; =3D&gt; in intro for =
5, unit
mentioned is days<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt; It should be weeks, I will =
fix
that.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>9: We can add (not exhaustive =
list):<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>- Modification of inodes already =
checked
by eek thread<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>- Vsvr move, snap revert, mirror,
backup/restore&#8230; when online eek is =
running<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>- Online eek when system is under =
load (at
what point is the thread stopped)<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>- =
Performance<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dred face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:red'>JOBI&gt; =
ok<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> =
<st1:PersonName
w:st=3D"on">Jobi Ariyamannil</st1:PersonName> <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Thursday, July 26, =
2007 9:41
AM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> Raj Kumar; dl-Design =
Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Thanks again, Raj. See my comments =
below.<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<ol style=3D'margin-top:0in' start=3D1 type=3D1>
 <li class=3DMsoNormal style=3D'color:navy;mso-list:l0 level1 =
lfo3'><font size=3D2
     color=3Dnavy face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'>We
     have some code in place to take care of this situation (setting the
     filesystem version correctly after revert) already, but that is not =
fool
     proof.&nbsp; Since we may make more layout changes in future, I =
thought to
     fix this issue correctly.&nbsp; So no issues with older snapshots, =
they
     will work.<o:p></o:p></span></font></li>
 <li class=3DMsoNormal style=3D'color:navy;mso-list:l0 level1 =
lfo3'><font size=3D2
     color=3Dnavy face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'>If
     the target does not understand the layout version of the source
     filesystem, remote mirroring will fail and they need to upgrade the
     software on the target to a release which understands the =
layout.&nbsp;
     Since some of the filesystem hardening work are specific to certain
     layouts, certain times we need to force that.&nbsp; I am not sure =
how
     frequently we encounter the situation of source and target running
     different releases in the field.&nbsp; Let me think and discuss =
this issue
     some more.<o:p></o:p></span></font></li>
</ol>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Regards,<o:p></o:p></span></font></p=
>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Jobi<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<div>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabindex=3D-1>

</span></font></div>

<p class=3DMsoNormal><b><font size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font =
size=3D2
face=3DTahoma><span style=3D'font-size:10.0pt;font-family:Tahoma'> Raj =
Kumar <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Thursday, July 26, =
2007 8:59
AM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Jobi
 Ariyamannil</st1:PersonName>; dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: func spec =
for online
eek</span></font><o:p></o:p></p>

</div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<div id=3DidOWAReplyText21844>

<div>

<p class=3DMsoNormal><font size=3D2 color=3Dblack face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:black'>Looks good. Few =
comments:</span></font><o:p></o:p></p>

</div>

<div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'>&nbsp;<o:p></o:p></span></font></p>

</div>

<div>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>* Section 5.5:&nbsp; Track version while taking =
snapshot:
Can we still support reverting to older snapshots since they wont have =
version
information?</span></font><o:p></o:p></p>

</div>

<div>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>* This change will force the DMIP customers to =
upgrade their
target DMIP cluster to Zonda. Currently they don't need to it. No big =
deal but
need to make sure support is aware of this.</span></font><o:p></o:p></p>

</div>

</div>

<div>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'><o:p>&nbsp;</o:p></span></font></p>

<div class=3DMsoNormal align=3Dcenter style=3D'text-align:center'><font =
size=3D3
face=3D"Times New Roman"><span style=3D'font-size:12.0pt'>

<hr size=3D2 width=3D"100%" align=3Dcenter tabIndex=3D-1>

</span></font></div>

<p class=3DMsoNormal style=3D'margin-bottom:12.0pt'><b><font size=3D2 =
face=3DTahoma><span
style=3D'font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</spa=
n></font></b><font
size=3D2 face=3DTahoma><span =
style=3D'font-size:10.0pt;font-family:Tahoma'> <st1:PersonName
w:st=3D"on">Jobi Ariyamannil</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tue 7/24/2007 8:33 =
PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> dl-Design Review<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> func spec for =
online eek</span></font><o:p></o:p></p>

</div>

<div>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Hi,</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'>&nbsp;<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Please review the attached func spec for online eek =
feature
planned for zonda.</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>We plan to deliver the framework and online =
detection/repair
of duplicate blocks and incorrect refcounts (live =
bit).</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Please let me know any comments you may =
have.</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'>&nbsp;<o:p></o:p></span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Regards,</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Jobi</span></font><o:p></o:p></p>

</div>

</div>

</div>

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