Mailing-List: contact users-help@tomcat.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Tomcat Users List" <users@tomcat.apache.org>
Received-SPF: pass (asf.osuosl.org: domain of edoardo.causarano@gmail.com
 designates 66.249.92.169 as permitted sender)
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
        s=beta; d=gmail.com;
        h=received:mime-version:in-reply-to:references:content-type:message-id:content-transfer-encoding:from:subject:date:to:x-mailer;
        b=WxOblwFOnzAAUzpXhAvMAlFnKUDEHyy9H0BOz1FTLu8MKklMR9VKwoWQwQrRKN3yzp/x5pbFXdp5xrfmxn/EE78P5367NvF5QYEPgNfbDeto58aefBKj00DWRLlBkIegtlS0//m8GAbU4xiB3qKHQTtH9TSB23whcGSUXqCH/ik=
Mime-Version: 1.0 (Apple Message framework v752.2)
In-Reply-To: <44F88837.6090309@hanik.com>
References: <37B5E0DF-70C4-49D2-B7AD-8E8F81CDC084@gmail.com>
 <44F88837.6090309@hanik.com>
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
Message-Id: <97D89BB7-FDDA-4C68-A935-6A24ED3A3B24@gmail.com>
Content-Transfer-Encoding: 7bit
From: Edoardo Causarano <edoardo.causarano@gmail.com>
Subject: Re: Clustering with mod_jk
Date: Fri, 1 Sep 2006 21:54:36 +0200
To: "Tomcat Users List" <users@tomcat.apache.org>

Using mpm_worker gave less impressive results; I'd say about 1/2, a  
much worse load average (way more than 5), and lots of swap. Seems  
like prefork works better on linux and I'm surprised. Anyway,  
assuming that I got the maxProcessors wrong I should have seen queues  
building up @ 150*4 instead they start < 50% that value.

The thing that makes me think it's a mod_jk issue is the fact that  
suddenly all request flow locks onto a node and stays busy until I  
restart apache.

e

On 01/set/06, at 21:21GMT+02:00, Filip Hanik - Dev Lists wrote:

> since you are using prefork, you must set cachesize=1 for your  
> workers.properties file.
> However, you have 4096 MaxClients, in order to serve this up in  
> tomcat, your JK connector should have maxProcessors="4096".
> An alternative, and safe solution, although much less performance,  
> is to set "MaxRequestsPerChild 1", this way you can get away with  
> MaxClients 4096 and still have a much less maxProcessor value on  
> Tomcat
>
> Filip
>
>
> Edoardo Causarano wrote:
>> Hello List,
>>
>> scenario:
>>
>> - 4 node tc 5.0.28 vertical cluster ( :-| same server... still  
>> testing, but it could have been 8) listening on ajp
>> <Connector address="x.x.x.x" port="8009"
>>     maxProcessors="150" minProcessors="50"
>>     protocol="AJP/1.3"  
>> protocolHandlerClassName="org.apache.jk.server.JkCoyoteHandler"
>>     redirectPort="8443">
>>
>> - 1 httpd 2.0.52 with mod_ajp 1.2.15 and prefork config on RH AS4,  
>> kernel 2.6.9-5.EL
>>     sticky sessions are disabled to avoid stress scripts hitting  
>> only one node
>>
>> <IfModule prefork.c>
>>     StartServers       40
>>     MinSpareServers    80
>>     MaxSpareServers    280
>>     ServerLimit        4096
>>     MaxClients         4096
>>     MaxRequestsPerChild  4096
>> </IfModule>
>>
>> - 1 application where a couple of thousand users should hammer the  
>> app deployed on the webapp
>>
>> What happens is the app takes the stresser for a ride until 240  
>> circa users then starts to die; jkmonitor sees linear increase on  
>> busy and max requests on only one node and pages hang; disabling  
>> the node moves the hung request handling to the next node.
>>
>> Where's the bottleneck? Any known bug in mod_jk? Should I increase  
>> threads on the tomcat nodes?
>>
>> Tnx,
>> e
>>
>>
>>
>>
>>
>> ---------------------------------------------------------------------
>> To start a new topic, e-mail: users@tomcat.apache.org
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>> --No virus found in this incoming message.
>> Checked by AVG Free Edition.
>> Version: 7.1.405 / Virus Database: 268.11.7/435 - Release Date:  
>> 8/31/2006
>>
>>
>
>
> ---------------------------------------------------------------------
> To start a new topic, e-mail: users@tomcat.apache.org
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>


---------------------------------------------------------------------
To start a new topic, e-mail: users@tomcat.apache.org
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org