X-MimeOLE: Produced By Microsoft Exchange V6.5
Received: by onstor-exch02.onstor.net 
	id <01C836CC.4A762E61@onstor-exch02.onstor.net>; Tue, 4 Dec 2007 15:20:43 -0800
MIME-Version: 1.0
Content-Type: multipart/alternative;
	boundary="----_=_NextPart_001_01C836CC.4A762E61"
Content-class: urn:content-classes:message
Subject: RE: Filesystem questions from Ithaka
Date: Tue, 4 Dec 2007 15:20:42 -0800
Message-ID: <BB375AF679D4A34E9CA8DFA650E2B04E06E5B739@onstor-exch02.onstor.net>
In-Reply-To: <BB375AF679D4A34E9CA8DFA650E2B04E06E5B707@onstor-exch02.onstor.net>
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
Thread-Topic: Filesystem questions from Ithaka
Thread-Index: Acg2OWDqMgx6Z91ZRNuDRbERC0F9kQAAfQbQACJ1xkMAAIuyUAAAPhsQAAAkYSAAAC8t8AAAlkBg
References: <BB375AF679D4A34E9CA8DFA650E2B04E06E2DD58@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E5B19F@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E2DD5D@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E5B6EA@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E5B6F7@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E5B6FF@onstor-exch02.onstor.net> <BB375AF679D4A34E9CA8DFA650E2B04E06E5B707@onstor-exch02.onstor.net>
From: "Jobi Ariyamannil" <jobi.ariyamannil@onstor.com>
To: "John Keiffer" <john.keiffer@onstor.com>,
	"Dave Limato" <dave.limato@onstor.com>,
	"Dennis Arellano" <dennis.arellano@onstor.com>,
	"Michael Ridley" <mridley@onstor.com>,
	"dl-cstech" <dl-cstech@onstor.com>
Cc: "Carlos Mora" <carlos.mora@onstor.com>,
	"Raghu Murthy" <raghu.murthy@onstor.com>

This is a multi-part message in MIME format.

------_=_NextPart_001_01C836CC.4A762E61
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: quoted-printable

All those options are needed and we use them sometimes during evals or
in specific configurations.

In general, everybody must use the default layout type 0.  The web page
was pointed to because it gives some idea on our allocation policies.

No need of making any changes in the system configuration.

=20

Regards,

Jobi

=20

________________________________

From: John Keiffer=20
Sent: Tuesday, December 04, 2007 3:02 PM
To: Dave Limato; Dennis Arellano; Michael Ridley; Jobi Ariyamannil;
dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

=20

I'll file a defect to see that it gets properly addressed then.

=20

-John

=20

________________________________

From: Dave Limato=20
Sent: Tuesday, December 04, 2007 3:00 PM
To: John Keiffer; Dennis Arellano; Michael Ridley; Jobi Ariyamannil;
dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

=20

Michael,

=20

Don't mess with this in a live environment. That page was current back
in 1.3 days (not even sure it was supported then). I think the behavior
now might even be different than what is described on that page.

=20

John, I would agree with it being a defect. It should be hidden until
fully tested.

________________________________

From: John Keiffer=20
Sent: Tuesday, December 04, 2007 2:54 PM
To: Dennis Arellano; Michael Ridley; Jobi Ariyamannil; dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

=20

If it was intentionally left out and only for internal use, then it
sounds like this is a bug. It looks like it should either be in debug
builds only, or perhaps as a diag cmd. Currently it is in the cmd help
of the CLI on OPT builds, which would be a defect right?

=20

g11r9> volume modify vol

  [OPTIONS  [-a LAYOUTTYPE] [-A ATIMEUPDATES] [-c CHARSUBST] [-d
ARRAYORDEVICE] [-e SHAREDREAD] [-g MINAUTOGROW] [-h HIGHWATERMARK] [-j
SECURITYSTYLE] [-l MINLUNSIZE] [-L LANGUAGE] [-n AUTOREMOVESNAPS] [-o
OPLOCKS] [-p NEWVOLNAME] [-q HARDQUOTA] [-r REMOVEARRAY] [-s SOFTQUOTA]
[-S STABILITY] [-t CHARSUBSTTABLE] [-u MAXLUNSIZE]

=20

________________________________

From: Dennis Arellano=20
Sent: Tuesday, December 04, 2007 2:47 PM
To: Michael Ridley; Jobi Ariyamannil; dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

=20

Hi Michael,

=20

The -a option was intentionally left out of the Command Reference since
it is for internal use only.

=20

Dennis

=20

________________________________

From: Michael Ridley=20
Sent: Tuesday, December 04, 2007 2:30 PM
To: Jobi Ariyamannil; dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

=20

Follow up question on this.  I looked at the wiki and it states that you
can change the layout type with the vol create/vol modify -a command.  I
logged into a test filer running 3.0.1.1 and if I do a

=20

vol modify volname ?

=20

it does show [ -a LAYOUTTYPE] as an option, but it's not in the command
reference and when I actually run it I get:

=20

cslab3 MICHAEL> vol modify mikevol -a 0
Invalid option (-a).

Is this option deprecated and if so do we only support the default type
0 allocation?  Thanks!

=20

-m

=20

________________________________

From: Jobi Ariyamannil
Sent: Tue 12/4/2007 1:09 AM
To: Michael Ridley; dl-cstech
Cc: Carlos Mora; Raghu Murthy
Subject: RE: Filesystem questions from Ithaka

Hi,

=20

Please see the wiki page http://wiki/wiki/FS/Allocation which explains
our filesystem allocation policies.

There is no default size for extents.  The filesystem has no knowledge
of the LUN boundaries.

=20

Regards,

Jobi

=20

________________________________

From: Michael Ridley=20
Sent: Monday, December 03, 2007 9:49 PM
To: dl-cstech
Subject: Filesystem questions from Ithaka

=20

Hi all-

=20

Following the exciting discussion of Max Queue Depth last week, I have
some follow-up questions from the folks and Ithaka.  Cut and pasted for
your reading enjoyment.  If anyone knows about our filesystem allocation
policies I'd appreciate the input.

=20

Customer Questions:

=20

Can you please clarify what threshold the onstor uses to determine
whether data should be committed sequentially (all to contigous entents
on the same LUN) vs randomly (to a random extents on various luns)? Is
it based on the extent size of the EverON volume (ie single extent vs
multi-extent IO)? If so, what is the default extent size.

Secondly, does the filesystem processor attempt to use a contiguous
region on each LUN? By way of example, if there are four luns of 25
extents each within an empty volume, would an incoming write request use
extents completely at random (15, 87, 92, 44, etc), or would it use the
next extent from each lun (1 in each case, then 2, then 3). I understand
that this is not striping, and an incoming sequential write of 10
extents could make the volumes uneven in capacity used, but I'm trying
to understand how randomly the IO is, and the implications on optimal
storage layout.

Thanks!

=20

-m


------_=_NextPart_001_01C836CC.4A762E61
Content-Type: text/html;
	charset="us-ascii"
Content-Transfer-Encoding: quoted-printable

<html xmlns:v=3D"urn:schemas-microsoft-com:vml" =
xmlns:o=3D"urn:schemas-microsoft-com:office:office" =
xmlns:w=3D"urn:schemas-microsoft-com:office:word" =
xmlns:st1=3D"urn:schemas-microsoft-com:office:smarttags" =
xmlns=3D"http://www.w3.org/TR/REC-html40">

<head>
<meta http-equiv=3DContent-Type content=3D"text/html; =
charset=3Dus-ascii">
<meta name=3DGenerator content=3D"Microsoft Word 11 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]--><o:SmartTagType
 namespaceuri=3D"urn:schemas-microsoft-com:office:smarttags" =
name=3D"PersonName"/>
<!--[if !mso]>
<style>
st1\:*{behavior:url(#default#ieooui) }
</style>
<![endif]-->
<style>
<!--
font-face=0A=
	{font-family:Tahoma;}

 /* Font Definitions */
 @font-face
	{font-family:Tahoma;
	panose-1:2 11 6 4 3 5 4 4 2 4;}
 /* Style Definitions */
 p.MsoNormal, li.MsoNormal, div.MsoNormal
	{margin:0in;
	margin-bottom:.0001pt;
	font-size:12.0pt;
	font-family:"Times New Roman";}
a:link, span.MsoHyperlink
	{color:blue;
	text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
	{color:purple;
	text-decoration:underline;}
span.emailstyle17
	{font-family:Arial;
	color:navy;}
span.EmailStyle18
	{mso-style-type:personal;
	font-family:Arial;
	color:navy;}
span.EmailStyle19
	{mso-style-type:personal;
	font-family:Arial;
	color:navy;}
span.EmailStyle20
	{mso-style-type:personal;
	font-family:Arial;
	color:navy;}
span.EmailStyle21
	{mso-style-type:personal;
	font-family:Arial;
	color:navy;}
span.EmailStyle22
	{mso-style-type:personal-reply;
	font-family:Arial;
	color:navy;}
@page Section1
	{size:8.5in 11.0in;
	margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
	{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
 <o:shapedefaults v:ext=3D"edit" spidmax=3D"1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
 <o:shapelayout v:ext=3D"edit">
  <o:idmap v:ext=3D"edit" data=3D"1" />
 </o:shapelayout></xml><![endif]-->
</head>

<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'>All those options are needed and we =
use
them sometimes during evals or in specific =
configurations.<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'>In general, everybody must use the =
default
layout type 0. &nbsp;The web page was pointed to because it gives some =
idea on our
allocation policies.<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'>No need of making any changes in =
the system
configuration.<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'>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>

<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'> John =
Keiffer <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tuesday, December =
04, 2007
3:02 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Dave
 Limato</st1:PersonName>; Dennis Arellano; Michael Ridley; =
<st1:PersonName
w:st=3D"on">Jobi Ariyamannil</st1:PersonName>; dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</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'>I&#8217;ll file a defect to see =
that it
gets properly addressed then.<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'>-John<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">Dave Limato</st1:PersonName> <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tuesday, December =
04, 2007
3:00 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> John Keiffer; Dennis =
Arellano;
Michael Ridley; <st1:PersonName w:st=3D"on">Jobi =
Ariyamannil</st1:PersonName>;
dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</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'>Michael,<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'>Don&#8217;t mess with this in a =
live
environment. That page was current back in 1.3 days (not even sure it =
was
supported then). I think the behavior now might even be different than =
what is
described on that page.<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'>John, I would agree with it being a
defect. It should be hidden until fully =
tested.<o:p></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">John Keiffer</st1:PersonName> <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tuesday, December =
04, 2007
2:54 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> Dennis Arellano; =
Michael
Ridley; <st1:PersonName w:st=3D"on">Jobi Ariyamannil</st1:PersonName>; =
dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</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'>If it was intentionally left out =
and only
for internal use, then it sounds like this is a bug. It looks like it =
should
either be in debug builds only, or perhaps as a diag cmd. Currently it =
is in
the cmd help of the CLI on OPT builds, which would be a defect =
right?<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'>g11r9&gt; volume modify =
vol<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'>&nbsp; [OPTIONS&nbsp; [-a =
LAYOUTTYPE] [-A
ATIMEUPDATES] [-c CHARSUBST] [-d ARRAYORDEVICE] [-e SHAREDREAD] [-g
MINAUTOGROW] [-h HIGHWATERMARK] [-j SECURITYSTYLE] [-l MINLUNSIZE] [-L
LANGUAGE] [-n AUTOREMOVESNAPS] [-o OPLOCKS] [-p NEWVOLNAME] [-q =
HARDQUOTA] [-r
REMOVEARRAY] [-s SOFTQUOTA] [-S STABILITY] [-t CHARSUBSTTABLE] [-u =
MAXLUNSIZE]<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'> =
Dennis Arellano <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tuesday, December =
04, 2007
2:47 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> Michael Ridley; =
<st1:PersonName
w:st=3D"on">Jobi Ariyamannil</st1:PersonName>; dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</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'>Hi =
Michael,<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'>The &#8211;a option was =
intentionally left
out of the Command Reference since it is for internal use =
only.<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'>Dennis<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'> =
Michael Ridley <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Tuesday, December =
04, 2007
2:30 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> <st1:PersonName =
w:st=3D"on">Jobi
 Ariyamannil</st1:PersonName>; dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</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=3DidOWAReplyText54516>

<div>

<p class=3DMsoNormal><font size=3D2 color=3Dblack face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:black'>Follow up question on this.&nbsp; =
I
looked at the wiki and it states that you can change the layout type =
with the
vol create/vol modify -a command.&nbsp; I logged into a test filer =
running
3.0.1.1 and if I do a</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 color=3Dblack face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:black'>vol modify volname =
?</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'>it does show [ -a LAYOUTTYPE] as an option, but it's =
not in
the command reference and when I actually run it I =
get:</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=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'>cslab3 MICHAEL&gt; vol modify mikevol -a 0<br>
Invalid option (-a).<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'>Is this option deprecated and if so do we only =
support the
default type 0 allocation?&nbsp; Thanks!</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'>-m</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 12/4/2007 1:09 =
AM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> Michael Ridley; =
dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> <st1:PersonName =
w:st=3D"on">Carlos
 Mora</st1:PersonName>; <st1:PersonName w:st=3D"on">Raghu =
Murthy</st1:PersonName><br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> RE: Filesystem =
questions
from Ithaka</span></font><o:p></o:p></p>

</div>

<div>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>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 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Please see the wiki page <a
href=3D"http://wiki/wiki/FS/Allocation">http://wiki/wiki/FS/Allocation</a=
> which
explains our filesystem allocation =
policies.</span></font><o:p></o:p></p>

<p class=3DMsoNormal><font size=3D2 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>There is no default size for
extents.&nbsp; The filesystem has no knowledge of the LUN =
boundaries.</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 color=3Dnavy face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:navy'>Regards,</span></font><o:p></o:p></p=
>

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

<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'> =
Michael Ridley <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Monday, December =
03, 2007
9:49 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> dl-cstech<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> Filesystem =
questions from
Ithaka</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'>&nbsp;<o:p></o:p></span></font></p>

<div>

<p class=3DMsoNormal><font size=3D2 color=3Dblack face=3DArial><span =
style=3D'font-size:
10.0pt;font-family:Arial;color:black'>Hi =
all-</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'>Following the exciting discussion of Max Queue Depth =
last
week, I have some follow-up questions from the folks and Ithaka.&nbsp; =
Cut and
pasted for your reading enjoyment.&nbsp; If anyone knows about our =
filesystem
allocation policies I'd appreciate the =
input.</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'>Customer Questions:</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=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'>Can you please clarify what threshold the onstor uses to =
determine
whether data should be committed sequentially (all to contigous entents =
on the
same LUN) vs randomly (to a random extents on various luns)? Is it based =
on the
extent size of the EverON volume (ie single extent vs multi-extent IO)? =
If so,
what is the default extent size.<br>
<br>
Secondly, does the filesystem processor attempt to use a contiguous =
region on
each LUN? By way of example, if there are four luns of 25 extents each =
within
an empty volume, would an incoming write request use extents completely =
at
random (15, 87, 92, 44, etc), or would it use the next extent from each =
lun (1
in each case, then 2, then 3). I understand that this is not striping, =
and an
incoming sequential write of 10 extents could make the volumes uneven in
capacity used, but I'm trying to understand how randomly the IO is, and =
the
implications on optimal storage layout.<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'>Thanks!</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'>-m</span></font><o:p></o:p></p>

</div>

</div>

</div>

</body>

</html>

------_=_NextPart_001_01C836CC.4A762E61--
