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Posted to users@tomcat.apache.org by Jayaram Ponnusamy <ja...@gmail.com> on 2019/12/05 08:19:27 UTC
Tomcat Crashed when the concurrent Users reached 150
Hello,
We are using apache 2.2.21 on RHEL6.9 and in Backend we are using Tomcat
AppServer with JavaBased CMS.
Our Server Architecture is *(F5 [For Load Balance] -> Apache WebServer [For
Redirection & URL Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
We are using Apache to connect Tomcat by MOD_JK and mapping the URL
(Attached VirtualHost.conf), and No applications/code are running on
WebServers.
1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers)
2. Two WebServers (4 CPU & 8GB RAM on Each Servers)
*PROBLEM:*
When the Child Process count is reached / crossed 200 like below then site
is not accessible when the child processes reached 300 or More than site
crashed and then we bring the site back by restarting Tomcat & Apache HTTP.
Kindly please check my configuration and help to allow at-least 500
concurrent users.
*CONFIGURATION:*
* httpd.conf*
<IfModule prefork.c>
StartServers 80
ServerLimit 3500
MaxClients 3500
MaxRequestsPerChild 0
</IfModule>
<IfModule worker.c>
StartServers 6
MaxClients 230
MinSpareThreads 75
MaxSpareThreads 150
ThreadsPerChild 25
MaxRequestsPerChild 0
</IfModule>
*Tomcat:*
<Connector port="9090" protocol="HTTP/1.1" redirectPort="8443"
URIEncoding="UTF-8" emptySessionPath="true" maxThreads="600"
minSpareThreads="10" connectionTimeout="-1" />
<Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
connectionTimeout="20000" acceptCount="2000" />
--
--
*Thanks & Regards,*
*Jayaram Ponnusamy*
Mobile: +974-5512-3315
Re: Tomcat Crashed when the concurrent Users reached 150
Posted by Mark Thomas <ma...@apache.org>.
On 05/12/2019 08:19, Jayaram Ponnusamy wrote:
> Hello,
> We are using apache 2.2.21 on RHEL6.9 and in Backend we are using Tomcat
> AppServer with JavaBased CMS.
> Our Server Architecture is *(F5 [For Load Balance] -> Apache WebServer [For
> Redirection & URL Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
>
>
> We are using Apache to connect Tomcat by MOD_JK and mapping the URL
> (Attached VirtualHost.conf), and No applications/code are running on
> WebServers.
>
> 1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers)
> 2. Two WebServers (4 CPU & 8GB RAM on Each Servers)
Tomcat version?
mod_jk version?
Mark
>
> *PROBLEM:*
> When the Child Process count is reached / crossed 200 like below then site
> is not accessible when the child processes reached 300 or More than site
> crashed and then we bring the site back by restarting Tomcat & Apache HTTP.
> Kindly please check my configuration and help to allow at-least 500
> concurrent users.
>
> *CONFIGURATION:*
> * httpd.conf*
> <IfModule prefork.c>
> StartServers 80
> ServerLimit 3500
> MaxClients 3500
> MaxRequestsPerChild 0
> </IfModule>
> <IfModule worker.c>
> StartServers 6
> MaxClients 230
> MinSpareThreads 75
> MaxSpareThreads 150
> ThreadsPerChild 25
> MaxRequestsPerChild 0
> </IfModule>
>
> *Tomcat:*
> <Connector port="9090" protocol="HTTP/1.1" redirectPort="8443"
> URIEncoding="UTF-8" emptySessionPath="true" maxThreads="600"
> minSpareThreads="10" connectionTimeout="-1" />
> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> connectionTimeout="20000" acceptCount="2000" />
>
>
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Re: Tomcat Crashed when the concurrent Users reached 150
Posted by Jayaram Ponnusamy <ja...@gmail.com>.
Thanks a Lot Mark
On Mon, Dec 9, 2019 at 2:22 PM Mark Thomas <ma...@apache.org> wrote:
> On 09/12/2019 06:41, Jayaram Ponnusamy wrote:
> > Thanks for your Valuable Comments:
> > We are using Apache Tomcat/8.0.50 and Mod_JK mod_jk/1.2.28
> >
> > The Above configuration made by some consultant. We are in the
> situation to
> > correct all the things to make it for high availability.
> > Also we are in the process of upgrading the apache to 2.4.25 with mod_jk/
> > 1.2.42. And Event MPM instead of Prefork.
> >
> > Please let us know do we need to use worker MPM also or EVENT MPM is
> fine?
> > If Event MPM with below Configuration then how many concurrent users can
> > access the site and what are the relevant changes needs to be done on
> > Tomcat Side?
> > On Tomcat Servers We have 16GB RAM with 8CPU [Two Nodes]
> >
> > # event MPM
> > <IfModule event.c>
> > StartServers 1
> > ServerLimit 7
> > MinSpareThreads 250
> > MaxSpareThreads 2500
> > ThreadsPerChild 500
> > ThreadLimit 500
> > MaxRequestWorkers 3500
> > MaxConnectionsPerChild 0
> > </IfModule>
> >
> >
> > # Tomcat Configuration
> > <Connector port="9090" protocol="HTTP/1.1" redirectPort="8443"
> > URIEncoding="UTF-8" emptySessionPath="true" maxThreads="600"
> > minSpareThreads="10" connectionTimeout="-1" />
> > <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> > URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> > connectionTimeout="20000" acceptCount="2000" />
> >
> >
> > # Tomcat Configuration
> > -Xms2048M -Xmx6144M -XX:PermSize=1024m -XX:MaxPermSize=2048m
> >
> >
> >
> >
> > On Thu, Dec 5, 2019 at 7:27 PM Christopher Schultz <
> > chris@christopherschultz.net> wrote:
> >
> > Jayaram,
> >
> > On 12/5/19 03:19, Jayaram Ponnusamy wrote:
> >>>> We are using apache 2.2.21 on RHEL6.9 and in Backend we are using
> >>>> Tomcat AppServer with JavaBased CMS. Our Server Architecture is
> >>>> *(F5 [For Load Balance] -> Apache WebServer [For Redirection & URL
> >>>> Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
> >
> > That version of Apache httpd is pretty old and unsupported. RHEL 6.9
> > is also out of support (if I'm reading their Wikipedia page
> > correctly). You may want to upgrade everything while you are looking
> > at all this.
> >
> >>>> We are using Apache to connect Tomcat by MOD_JK and mapping the
> >>>> URL (Attached VirtualHost.conf), and No applications/code are
> >>>> running on WebServers.
> >>>>
> >>>> 1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers) 2. Two
> >>>> WebServers (4 CPU & 8GB RAM on Each Servers)
> >>>>
> >>>> *PROBLEM:* When the Child Process count is reached / crossed 200
> >>>> like below then site is not accessible
> >
> > Do you mean that new connections from httpd -> Tomcat cannot be made?
> >
> >>>> when the child processes reached 300 or More than site crashed
> >
> > Please define "crashed". Got an exception? JVM crash (with hs_pid*
> > file)? Kernel panic?
> >
> >>>> and then we bring the site back by restarting Tomcat & Apache
> >>>> HTTP.
> >
> > Do you need to restart httpd? Or only Tomcat? Or will restarting httpd
> > work?
> >
> >>>> Kindly please check my configuration and help to allow at-least
> >>>> 500 concurrent users.
> >>>>
> >>>> *CONFIGURATION:* * httpd.conf* <IfModule prefork.c> StartServers
> >>>> 80 ServerLimit 3500 MaxClients 3500 MaxRequestsPerChild 0
> >>>> </IfModule> <IfModule worker.c> StartServers 6 MaxClients 230
> >>>> MinSpareThreads 75 MaxSpareThreads 150 ThreadsPerChild 25
> >>>> MaxRequestsPerChild 0 </IfModule>
> >
> > Which MPM are you actually using? You have listed both prefork and
> > worker. AFAICT you have to pick one at runtime.
> >
> > For prefork, the maximum number of connections you should expect to be
> > made to each Tomcat backend is 3500 (the value of MaxClients).
> >
> > For worker, the maximum number of connections you should expect to be
> > made to each Tomcat backend is 230.
> >
> >>>> *Tomcat:* <Connector port="9090" protocol="HTTP/1.1"
> >>>> redirectPort="8443" URIEncoding="UTF-8" emptySessionPath="true"
> >>>> maxThreads="600" minSpareThreads="10" connectionTimeout="-1" />
> >>>> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> >>>> URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> >>>> connectionTimeout="20000" acceptCount="2000" />
> >
> > Note that AJP connections are expected to be persistent; they don't
> > close when the request has completed. They don't even really do "keep
> > alive" in the same sense as HTTP keepalive. It's more like "always
> > keepalive". Once an httpd process opens a connection to a Tomcat
> > instance, that connection will remain open for quite a while as long
> > as requests continue to be made.
> >
> > If you are using prefork MPM, the the version of Tomcat you are using
> > is critical to understanding what is happening, here. If you are using
> > a BIO-based connector, then you will need to increase the number of
> > threads on each Tomcat server from 600 to 3500.
> >
> > If you are using the worker MPM, then your Tomcat should be able to
> > handle the 230 maximum connections configured there.
>
> TL;DR - Try switching to the NIO AJP connector on Tomcat.
>
> Take a look at this session I uploaded from TomcatCon London. You
> probably want to start around 35:00 and the topic of thread
> exhaustion.
>
> https://youtu.be/2QYWp1k5QQM
>
> Mark
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
--
*Thanks & Regards,*
*Jayaram Ponnusamy*
Re: Tomcat Crashed when the concurrent Users reached 150
Posted by Mark Thomas <ma...@apache.org>.
On 09/12/2019 06:41, Jayaram Ponnusamy wrote:
> Thanks for your Valuable Comments:
> We are using Apache Tomcat/8.0.50 and Mod_JK mod_jk/1.2.28
>
> The Above configuration made by some consultant. We are in the
situation to
> correct all the things to make it for high availability.
> Also we are in the process of upgrading the apache to 2.4.25 with mod_jk/
> 1.2.42. And Event MPM instead of Prefork.
>
> Please let us know do we need to use worker MPM also or EVENT MPM is fine?
> If Event MPM with below Configuration then how many concurrent users can
> access the site and what are the relevant changes needs to be done on
> Tomcat Side?
> On Tomcat Servers We have 16GB RAM with 8CPU [Two Nodes]
>
> # event MPM
> <IfModule event.c>
> StartServers 1
> ServerLimit 7
> MinSpareThreads 250
> MaxSpareThreads 2500
> ThreadsPerChild 500
> ThreadLimit 500
> MaxRequestWorkers 3500
> MaxConnectionsPerChild 0
> </IfModule>
>
>
> # Tomcat Configuration
> <Connector port="9090" protocol="HTTP/1.1" redirectPort="8443"
> URIEncoding="UTF-8" emptySessionPath="true" maxThreads="600"
> minSpareThreads="10" connectionTimeout="-1" />
> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> connectionTimeout="20000" acceptCount="2000" />
>
>
> # Tomcat Configuration
> -Xms2048M -Xmx6144M -XX:PermSize=1024m -XX:MaxPermSize=2048m
>
>
>
>
> On Thu, Dec 5, 2019 at 7:27 PM Christopher Schultz <
> chris@christopherschultz.net> wrote:
>
> Jayaram,
>
> On 12/5/19 03:19, Jayaram Ponnusamy wrote:
>>>> We are using apache 2.2.21 on RHEL6.9 and in Backend we are using
>>>> Tomcat AppServer with JavaBased CMS. Our Server Architecture is
>>>> *(F5 [For Load Balance] -> Apache WebServer [For Redirection & URL
>>>> Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
>
> That version of Apache httpd is pretty old and unsupported. RHEL 6.9
> is also out of support (if I'm reading their Wikipedia page
> correctly). You may want to upgrade everything while you are looking
> at all this.
>
>>>> We are using Apache to connect Tomcat by MOD_JK and mapping the
>>>> URL (Attached VirtualHost.conf), and No applications/code are
>>>> running on WebServers.
>>>>
>>>> 1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers) 2. Two
>>>> WebServers (4 CPU & 8GB RAM on Each Servers)
>>>>
>>>> *PROBLEM:* When the Child Process count is reached / crossed 200
>>>> like below then site is not accessible
>
> Do you mean that new connections from httpd -> Tomcat cannot be made?
>
>>>> when the child processes reached 300 or More than site crashed
>
> Please define "crashed". Got an exception? JVM crash (with hs_pid*
> file)? Kernel panic?
>
>>>> and then we bring the site back by restarting Tomcat & Apache
>>>> HTTP.
>
> Do you need to restart httpd? Or only Tomcat? Or will restarting httpd
> work?
>
>>>> Kindly please check my configuration and help to allow at-least
>>>> 500 concurrent users.
>>>>
>>>> *CONFIGURATION:* * httpd.conf* <IfModule prefork.c> StartServers
>>>> 80 ServerLimit 3500 MaxClients 3500 MaxRequestsPerChild 0
>>>> </IfModule> <IfModule worker.c> StartServers 6 MaxClients 230
>>>> MinSpareThreads 75 MaxSpareThreads 150 ThreadsPerChild 25
>>>> MaxRequestsPerChild 0 </IfModule>
>
> Which MPM are you actually using? You have listed both prefork and
> worker. AFAICT you have to pick one at runtime.
>
> For prefork, the maximum number of connections you should expect to be
> made to each Tomcat backend is 3500 (the value of MaxClients).
>
> For worker, the maximum number of connections you should expect to be
> made to each Tomcat backend is 230.
>
>>>> *Tomcat:* <Connector port="9090" protocol="HTTP/1.1"
>>>> redirectPort="8443" URIEncoding="UTF-8" emptySessionPath="true"
>>>> maxThreads="600" minSpareThreads="10" connectionTimeout="-1" />
>>>> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
>>>> URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
>>>> connectionTimeout="20000" acceptCount="2000" />
>
> Note that AJP connections are expected to be persistent; they don't
> close when the request has completed. They don't even really do "keep
> alive" in the same sense as HTTP keepalive. It's more like "always
> keepalive". Once an httpd process opens a connection to a Tomcat
> instance, that connection will remain open for quite a while as long
> as requests continue to be made.
>
> If you are using prefork MPM, the the version of Tomcat you are using
> is critical to understanding what is happening, here. If you are using
> a BIO-based connector, then you will need to increase the number of
> threads on each Tomcat server from 600 to 3500.
>
> If you are using the worker MPM, then your Tomcat should be able to
> handle the 230 maximum connections configured there.
TL;DR - Try switching to the NIO AJP connector on Tomcat.
Take a look at this session I uploaded from TomcatCon London. You
probably want to start around 35:00 and the topic of thread
exhaustion.
https://youtu.be/2QYWp1k5QQM
Mark
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Re: Tomcat Crashed when the concurrent Users reached 150
Posted by Jayaram Ponnusamy <ja...@gmail.com>.
Thanks for your Valuable Comments:
We are using Apache Tomcat/8.0.50 and Mod_JK mod_jk/1.2.28
The Above configuration made by some consultant. We are in the situation to
correct all the things to make it for high availability.
Also we are in the process of upgrading the apache to 2.4.25 with mod_jk/
1.2.42. And Event MPM instead of Prefork.
Please let us know do we need to use worker MPM also or EVENT MPM is fine?
If Event MPM with below Configuration then how many concurrent users can
access the site and what are the relevant changes needs to be done on
Tomcat Side?
On Tomcat Servers We have 16GB RAM with 8CPU [Two Nodes]
# event MPM
<IfModule event.c>
StartServers 1
ServerLimit 7
MinSpareThreads 250
MaxSpareThreads 2500
ThreadsPerChild 500
ThreadLimit 500
MaxRequestWorkers 3500
MaxConnectionsPerChild 0
</IfModule>
# Tomcat Configuration
<Connector port="9090" protocol="HTTP/1.1" redirectPort="8443"
URIEncoding="UTF-8" emptySessionPath="true" maxThreads="600"
minSpareThreads="10" connectionTimeout="-1" />
<Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
connectionTimeout="20000" acceptCount="2000" />
# Tomcat Configuration
-Xms2048M -Xmx6144M -XX:PermSize=1024m -XX:MaxPermSize=2048m
On Thu, Dec 5, 2019 at 7:27 PM Christopher Schultz <
chris@christopherschultz.net> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA256
>
> Jayaram,
>
> On 12/5/19 03:19, Jayaram Ponnusamy wrote:
> > We are using apache 2.2.21 on RHEL6.9 and in Backend we are using
> > Tomcat AppServer with JavaBased CMS. Our Server Architecture is
> > *(F5 [For Load Balance] -> Apache WebServer [For Redirection & URL
> > Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
>
> That version of Apache httpd is pretty old and unsupported. RHEL 6.9
> is also out of support (if I'm reading their Wikipedia page
> correctly). You may want to upgrade everything while you are looking
> at all this.
>
> > We are using Apache to connect Tomcat by MOD_JK and mapping the
> > URL (Attached VirtualHost.conf), and No applications/code are
> > running on WebServers.
> >
> > 1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers) 2. Two
> > WebServers (4 CPU & 8GB RAM on Each Servers)
> >
> > *PROBLEM:* When the Child Process count is reached / crossed 200
> > like below then site is not accessible
>
> Do you mean that new connections from httpd -> Tomcat cannot be made?
>
> > when the child processes reached 300 or More than site crashed
>
> Please define "crashed". Got an exception? JVM crash (with hs_pid*
> file)? Kernel panic?
>
> > and then we bring the site back by restarting Tomcat & Apache
> > HTTP.
>
> Do you need to restart httpd? Or only Tomcat? Or will restarting httpd
> work?
>
> > Kindly please check my configuration and help to allow at-least
> > 500 concurrent users.
> >
> > *CONFIGURATION:* * httpd.conf* <IfModule prefork.c> StartServers
> > 80 ServerLimit 3500 MaxClients 3500 MaxRequestsPerChild 0
> > </IfModule> <IfModule worker.c> StartServers 6 MaxClients 230
> > MinSpareThreads 75 MaxSpareThreads 150 ThreadsPerChild 25
> > MaxRequestsPerChild 0 </IfModule>
>
> Which MPM are you actually using? You have listed both prefork and
> worker. AFAICT you have to pick one at runtime.
>
> For prefork, the maximum number of connections you should expect to be
> made to each Tomcat backend is 3500 (the value of MaxClients).
>
> For worker, the maximum number of connections you should expect to be
> made to each Tomcat backend is 230.
>
> > *Tomcat:* <Connector port="9090" protocol="HTTP/1.1"
> > redirectPort="8443" URIEncoding="UTF-8" emptySessionPath="true"
> > maxThreads="600" minSpareThreads="10" connectionTimeout="-1" />
> > <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> > URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> > connectionTimeout="20000" acceptCount="2000" />
>
> Note that AJP connections are expected to be persistent; they don't
> close when the request has completed. They don't even really do "keep
> alive" in the same sense as HTTP keepalive. It's more like "always
> keepalive". Once an httpd process opens a connection to a Tomcat
> instance, that connection will remain open for quite a while as long
> as requests continue to be made.
>
> If you are using prefork MPM, the the version of Tomcat you are using
> is critical to understanding what is happening, here. If you are using
> a BIO-based connector, then you will need to increase the number of
> threads on each Tomcat server from 600 to 3500.
>
> If you are using the worker MPM, then your Tomcat should be able to
> handle the 230 maximum connections configured there.
>
> - -chris
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>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
--
*Thanks & Regards,*
*Jayaram Ponnusamy*
Mobile: +974-5512-3315
Re: Tomcat Crashed when the concurrent Users reached 150
Posted by Christopher Schultz <ch...@christopherschultz.net>.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Jayaram,
On 12/5/19 03:19, Jayaram Ponnusamy wrote:
> We are using apache 2.2.21 on RHEL6.9 and in Backend we are using
> Tomcat AppServer with JavaBased CMS. Our Server Architecture is
> *(F5 [For Load Balance] -> Apache WebServer [For Redirection & URL
> Mapping] -> Tomcat AppServer [Running a Java Based CMS]).*
That version of Apache httpd is pretty old and unsupported. RHEL 6.9
is also out of support (if I'm reading their Wikipedia page
correctly). You may want to upgrade everything while you are looking
at all this.
> We are using Apache to connect Tomcat by MOD_JK and mapping the
> URL (Attached VirtualHost.conf), and No applications/code are
> running on WebServers.
>
> 1. Two TomcatServers (8 CPU & 16GB RAM on Each Servers) 2. Two
> WebServers (4 CPU & 8GB RAM on Each Servers)
>
> *PROBLEM:* When the Child Process count is reached / crossed 200
> like below then site is not accessible
Do you mean that new connections from httpd -> Tomcat cannot be made?
> when the child processes reached 300 or More than site crashed
Please define "crashed". Got an exception? JVM crash (with hs_pid*
file)? Kernel panic?
> and then we bring the site back by restarting Tomcat & Apache
> HTTP.
Do you need to restart httpd? Or only Tomcat? Or will restarting httpd
work?
> Kindly please check my configuration and help to allow at-least
> 500 concurrent users.
>
> *CONFIGURATION:* * httpd.conf* <IfModule prefork.c> StartServers
> 80 ServerLimit 3500 MaxClients 3500 MaxRequestsPerChild 0
> </IfModule> <IfModule worker.c> StartServers 6 MaxClients 230
> MinSpareThreads 75 MaxSpareThreads 150 ThreadsPerChild 25
> MaxRequestsPerChild 0 </IfModule>
Which MPM are you actually using? You have listed both prefork and
worker. AFAICT you have to pick one at runtime.
For prefork, the maximum number of connections you should expect to be
made to each Tomcat backend is 3500 (the value of MaxClients).
For worker, the maximum number of connections you should expect to be
made to each Tomcat backend is 230.
> *Tomcat:* <Connector port="9090" protocol="HTTP/1.1"
> redirectPort="8443" URIEncoding="UTF-8" emptySessionPath="true"
> maxThreads="600" minSpareThreads="10" connectionTimeout="-1" />
> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443"
> URIEncoding="UTF-8" maxThreads="600" minSpareThreads="100"
> connectionTimeout="20000" acceptCount="2000" />
Note that AJP connections are expected to be persistent; they don't
close when the request has completed. They don't even really do "keep
alive" in the same sense as HTTP keepalive. It's more like "always
keepalive". Once an httpd process opens a connection to a Tomcat
instance, that connection will remain open for quite a while as long
as requests continue to be made.
If you are using prefork MPM, the the version of Tomcat you are using
is critical to understanding what is happening, here. If you are using
a BIO-based connector, then you will need to increase the number of
threads on each Tomcat server from 600 to 3500.
If you are using the worker MPM, then your Tomcat should be able to
handle the 230 maximum connections configured there.
- -chris
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