Mailing-List: contact users-help@trafficserver.apache.org; run by ezmlm
Precedence: bulk
Reply-To: users@trafficserver.apache.org
Received-SPF: neutral (nike.apache.org: local policy)
Message-ID: <4C3DE1C8.6080807@apache.org>
Date: Wed, 14 Jul 2010 10:11:52 -0600
From: Leif Hedstrom <zwoop@apache.org>
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US;
 rv:1.9.1.10) Gecko/20100621 Fedora/3.0.5-1.fc13 Thunderbird/3.0.5
MIME-Version: 1.0
To: users@trafficserver.apache.org
CC: Rob Maidment <Rob.Maidment@clearswift.com>
Subject: Re: why does cache hit rate tail off?
References: 
 <A4BA8388678A894CBDA0DF2767AA6B640D91C62BF2@EXCHANGEMBX.EUROPE.CLEARSWIFT.COM>
 <1C38D729-ED26-4A0F-B37D-674C0589CA69@apache.org>
 <A4BA8388678A894CBDA0DF2767AA6B640DA648B10A@EXCHANGEMBX.EUROPE.CLEARSWIFT.COM>
In-Reply-To: 
 <A4BA8388678A894CBDA0DF2767AA6B640DA648B10A@EXCHANGEMBX.EUROPE.CLEARSWIFT.COM>
Content-Type: multipart/alternative;
 boundary="------------060503070601010304040607"

This is a multi-part message in MIME format.
--------------060503070601010304040607
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

On 07/14/2010 10:02 AM, Rob Maidment wrote:
>
> The old (LRU) algorithm made little difference.
>
> I guess it could be that I’m simply exceeding the cache capacity.  The 
> test uses a working set of 2.24GB.  How do I configure the size of the 
> cache?
>

Two settings:

In etc/trafficserver/storage.config, you will see a line similar to

     var/trafficserver 140M


You'll want that closer to  2.24G I imagine :). For the RAM cache, the 
setting is in etc/trafficserver/records.config:

     CONFIG proxy.config.cache.ram_cache.size INT -1


The default (-1) means it'll calculate the RAM cache size based on the 
disk cache size; For every 1GB of disk cache, it uses 1MB of RAM cache 
(which is really small honestly). I'd definitely bump this up as much as 
your box can handle, but make sure to leave room for the connections and 
other buffers (setting this is a "trial and error", and is very 
application specific). Fwiw, an inactive connection consumes about 32KB 
of memory, and an active one doubles that (for additional buffers). SSL 
connections consumes even more memory. (I think this is an area where we 
might be able to improve too, patches are welcomed).

I hope any of this helps your benchmarks (really looking forward to see 
your results).

-- leif


--------------060503070601010304040607
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: 8bit

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
  <meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
On 07/14/2010 10:02 AM, Rob Maidment wrote:
<blockquote
 cite="mid:A4BA8388678A894CBDA0DF2767AA6B640DA648B10A@EXCHANGEMBX.EUROPE.CLEARSWIFT.COM"
 type="cite">
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <meta name="Generator" content="Microsoft Word 12 (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:"Cambria Math";
	panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
	{font-family:Calibri;
	panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
	{font-family:Tahoma;
	panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
	{font-family:Verdana;
	panose-1:2 11 6 4 3 5 4 4 2 4;}
 /* Style Definitions */
 p.MsoNormal, li.MsoNormal, div.MsoNormal
	{margin:0cm;
	margin-bottom:.0001pt;
	font-size:12.0pt;
	font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
	{mso-style-priority:99;
	color:blue;
	text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
	{mso-style-priority:99;
	color:purple;
	text-decoration:underline;}
p
	{mso-style-priority:99;
	mso-margin-top-alt:auto;
	margin-right:0cm;
	mso-margin-bottom-alt:auto;
	margin-left:0cm;
	font-size:12.0pt;
	font-family:"Times New Roman","serif";}
span.EmailStyle19
	{mso-style-type:personal-reply;
	font-family:"Calibri","sans-serif";
	color:#1F497D;}
.MsoChpDefault
	{mso-style-type:export-only;
	font-size:10.0pt;}
@page WordSection1
	{size:612.0pt 792.0pt;
	margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
	{page:WordSection1;}
-->
  </style><!--[if gte mso 9]><xml>
 <o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
 <o:shapelayout v:ext="edit">
  <o:idmap v:ext="edit" data="1" />
 </o:shapelayout></xml><![endif]-->
  <div class="WordSection1">
  <p class="MsoNormal"><span
 style="font-size: 11pt; font-family: &quot;Calibri&quot;,&quot;sans-serif&quot;; color: rgb(31, 73, 125);"><o:p> </o:p></span></p>
  <p class="MsoNormal"><span
 style="font-size: 11pt; font-family: &quot;Calibri&quot;,&quot;sans-serif&quot;; color: rgb(31, 73, 125);">The
old (LRU) algorithm made little difference.<o:p></o:p></span></p>
  <p class="MsoNormal"><span
 style="font-size: 11pt; font-family: &quot;Calibri&quot;,&quot;sans-serif&quot;; color: rgb(31, 73, 125);">I
guess it could be that I’m simply exceeding the cache capacity. 
The test uses a working set of 2.24GB.  How do I configure the size of
the
cache?</span></p>
  </div>
</blockquote>
<br>
Two settings:<br>
<br>
In etc/trafficserver/storage.config, you will see a line similar to<br>
<br>
    var/trafficserver 140M<br>
<br>
<br>
You'll want that closer to  2.24G I imagine :). For the RAM cache, the
setting is in etc/trafficserver/records.config:<br>
<br>
    CONFIG proxy.config.cache.ram_cache.size INT -1<br>
<br>
<br>
The default (-1) means it'll calculate the RAM cache size based on the
disk cache size; For every 1GB of disk cache, it uses 1MB of RAM cache
(which is really small honestly). I'd definitely bump this up as much
as your box can handle, but make sure to leave room for the connections
and other buffers (setting this is a "trial and error", and is very
application specific). Fwiw, an inactive connection consumes about 32KB
of memory, and an active one doubles that (for additional buffers). SSL
connections consumes even more memory. (I think this is an area where
we might be able to improve too, patches are welcomed).<br>
<br>
I hope any of this helps your benchmarks (really looking forward to see
your results).<br>
<br>
-- leif<br>
<br>
</body>
</html>

--------------060503070601010304040607--