X-MimeOLE: Produced By Microsoft Exchange V6.5
Received: by onstor-exch02.onstor.net 
	id <01C782C6.A283D0D3@onstor-exch02.onstor.net>; Thu, 19 Apr 2007 14:06:44 -0700
MIME-Version: 1.0
Content-Type: multipart/alternative;
	boundary="----_=_NextPart_001_01C782C6.A283D0D3"
Content-class: urn:content-classes:message
Subject: RE: Block size for NFS
Date: Thu, 19 Apr 2007 14:06:44 -0700
Message-ID: <BB375AF679D4A34E9CA8DFA650E2B04E0351BF06@onstor-exch02.onstor.net>
In-Reply-To: <BB375AF679D4A34E9CA8DFA650E2B04E0351BEDE@onstor-exch02.onstor.net>
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
Thread-Topic: Block size for NFS
Thread-Index: AceBic2Vf4Hru1jRQ8+esydCBD+yAgArNxRwACMKPcAAAIuP4A==
References: <BB375AF679D4A34E9CA8DFA650E2B04E0351BEDE@onstor-exch02.onstor.net>
From: "Maxim Kozlovsky" <maxim.kozlovsky@onstor.com>
To: "Rich LaReau" <rich.lareau@onstor.com>,
	"dl-cstech" <dl-cstech@onstor.com>
Cc: "Frontline Support" <support@cc.onstor.com>

This is a multi-part message in MIME format.

------_=_NextPart_001_01C782C6.A283D0D3
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: quoted-printable

It does not make sense to specify the read or write size to the value
less than the server can support. This value is the maximum read or
write that can be used. The client will send smaller reads and writes if
it wishes to do so. Rsize and wsize settings should not depend on
whether the workload is streaming or not.=20

=20

Setting the block size to 2k must have slowed down the things so the
"hang" does not happen anymore or is not noticeable (because it is slow
enough already).=20

________________________________

From: Rich LaReau=20
Sent: Thursday, April 19, 2007 1:53 PM
To: dl-cstech
Cc: Frontline Support
Subject: Block size for NFS

=20

=20

We had a recent case, 4944, where a customer was getting periodic
"hangs" on one of his vsvrs.  Normally traffic would run fine, then have
a couple minutes of extreme slow-down (never to zero and with no
crashes.)  It turned out that particular vsvr was hosting NFS Squid
server data (http cache) which contains zillions of tiny files.  They
fixed it by changing the nfs rw mount options to 2k, justified by more
"closely matching" the application's data.

=20

We recommend for "streaming" applications to set these mount options to
32k:

=20

http://wiki/wiki/Best_practices_for_NFS

=20

Would a Squid server application be considered "streaming?"  Could
somebody describe briefly why we recommend 32k (this seems to be the
standard recommendation for nfs mounts) and how setting that to 2k
affected the system?  I imagine that it would throttle down the overall
throughput, which is now fixing or masking whatever was getting
temporarily stuck.

=20

Thanks,

Rich

=20

=20

=20

-----Original Message-----
From: Raghu Murthy=20
Sent: Wednesday, April 18, 2007 8:58 PM
To: Rich LaReau
Subject: FW: [Silverpop Systems Inc] 4944: "df -h hangs for a period of
time then goes through" - New case comment.

=20

=20

=20

May be useful for your performance doc

--------------------

We have identified that our 3 response master servers, that write lots
of small files, is contributing to the problem. We have another
production environment that does more volume of files and quantity of
space and it's mounts are on onstor01, and does not have this problem.
We have adjusted the NFS parameters to 2k rw buffer size on the problem
servers.

----------------

=20

-----Original Message-----

From: dl-Customer Service Cases=20

Sent: Wednesday, April 18, 2007 12:18 AM

To: dl-Customer Service Cases

Subject: [Silverpop Systems Inc] 4944: "df -h hangs for a period of time
then goes through" - New case comment.

=20

=20

A new comment has been added to case 4944 by Bob Kelleher.

https://ssl.salesforce.com/50000000000mBx1AAE

=20

---------------- Comment: ----------------

After changing the r/w buff size on the clients, all has been quite
well.  We are investigating why this single VS has 3 to 4 time more
traffic than the other 4 combined, running on the other gateway.

=20

=20

=20

You can close this ticket, thanks for the buff size settings
recommendation.

=20

=20

=20

rk

=20


------_=_NextPart_001_01C782C6.A283D0D3
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=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]-->
<style>
<!--
 /* 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;}
p.MsoPlainText, li.MsoPlainText, div.MsoPlainText
	{margin:0in;
	margin-bottom:.0001pt;
	font-size:10.0pt;
	font-family:"Courier New";}
span.EmailStyle18
	{mso-style-type:personal-reply;
	font-family:Arial;
	color:navy;}
@page Section1
	{size:8.5in 11.0in;
	margin:1.0in 77.95pt 1.0in 77.95pt;}
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'>It does not make sense to specify =
the read
or write size to the value less than the server can support. This value =
is the <i><span
style=3D'font-style:italic'>maximum</span></i> read or write that can be =
used. The
client will send smaller reads and writes if it wishes to do so. Rsize =
and
wsize settings should not depend on whether the workload is streaming or =
not. <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'>Setting the block size to 2k must =
have
slowed down the things so the &#8220;hang&#8221; does not happen anymore =
or is
not noticeable (because it is slow enough already). =
<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'> Rich =
LaReau <br>
<b><span style=3D'font-weight:bold'>Sent:</span></b> Thursday, April 19, =
2007
1:53 PM<br>
<b><span style=3D'font-weight:bold'>To:</span></b> dl-cstech<br>
<b><span style=3D'font-weight:bold'>Cc:</span></b> Frontline Support<br>
<b><span style=3D'font-weight:bold'>Subject:</span></b> Block size for =
NFS</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=3DMsoPlainText><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>We had a recent case, 4944, where a customer was =
getting
periodic &quot;hangs&quot; on one of his vsvrs.&nbsp; Normally traffic =
would
run fine, then have a couple minutes of extreme slow-down (never to zero =
and
with no crashes.)&nbsp; It turned out that particular vsvr was hosting =
NFS
Squid server data (http cache) which contains zillions of tiny =
files.&nbsp;
They fixed it by changing the nfs rw mount options to 2k, justified by =
more
&quot;closely matching&quot; the application's =
data.<o:p></o:p></span></font></p>

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

<p class=3DMsoPlainText><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>We recommend for &quot;streaming&quot; applications =
to set
these mount options to 32k:<o:p></o:p></span></font></p>

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

<p class=3DMsoPlainText><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>http://wiki/wiki/Best_practices_for_NFS<o:p></o:p></sp=
an></font></p>

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

<p class=3DMsoPlainText><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Would a Squid server application be considered =
&quot;streaming?&quot;&nbsp;
Could somebody describe briefly why we recommend 32k (this seems to be =
the
standard recommendation for nfs mounts) and how setting that to 2k =
affected the
system?&nbsp; I imagine that it would throttle down the overall =
throughput,
which is now fixing or masking whatever was getting temporarily =
stuck.<o:p></o:p></span></font></p>

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

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

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

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

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

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>-----Original Message-----<br>
From: Raghu Murthy <br>
Sent: Wednesday, April 18, 2007 8:58 PM<br>
To: Rich LaReau<br>
Subject: FW: [Silverpop Systems Inc] 4944: &quot;df -h hangs for a =
period of
time then goes through&quot; - New case =
comment.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>May be useful for your performance =
doc<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>--------------------<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>We have identified that our 3 response master servers, that =
write lots
of small files, is contributing to the problem. We have another =
production
environment that does more volume of files and quantity of space and =
it's
mounts are on onstor01, and does not have this problem. We have adjusted =
the
NFS parameters to 2k rw buffer size on the problem =
servers.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>----------------<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>-----Original Message-----<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>From: dl-Customer Service Cases <o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>Sent: Wednesday, April 18, 2007 12:18 =
AM<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>To: dl-Customer Service Cases<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>Subject: [Silverpop Systems Inc] 4944: &quot;df -h hangs for a =
period
of time then goes through&quot; - New case =
comment.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>A new comment has been added to case 4944 by Bob =
Kelleher.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>https://ssl.salesforce.com/50000000000mBx1AAE<o:p></o:p></span></=
font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>---------------- Comment: =
----------------<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>After changing the r/w buff size on the clients, all has been =
quite
well.&nbsp; We are investigating why this single VS has 3 to 4 time more
traffic than the other 4 combined, running on the other =
gateway.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>You can close this ticket, thanks for the buff size settings
recommendation.<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'>rk<o:p></o:p></span></font></p>

<p class=3DMsoPlainText><font size=3D2 face=3D"Courier New"><span =
style=3D'font-size:
10.0pt'><o:p>&nbsp;</o:p></span></font></p>

</div>

</body>

</html>

------_=_NextPart_001_01C782C6.A283D0D3--
