Hi Pid,
Thanks for your comments!
I would like a representative metric of how many active threads are in
Tomcat at a given time. "currentBusyThreads" may or may not be a good
counter because at the time of poll, there is one current operation or none
- giving me a value or "1" or "0" consistently. And again, that may just
be the case. In the middle of the night, though, I sometimes get a
"currentBusyThreads=50" value, perhaps due to a spidering of the site or
another batch operation on the server.
What is "DaemonThreadCount=85" please? Is that the current size of the
ThreadPool? I looked at our server.xml, and an Executor ThreadPool is not
in use for the 8080 and 8443 HTTP connectors. Could that mean that idle
threads are not expired properly? So at one point, the thread pool size
could have gone up to 85.
--------------server.xml snippet:-------
<Connector port="8443"
clientAuth="false"
connectionTimeout="60000"
disableUploadTimeout="true"
emptySessionPath="true"
enableLookups="false"
maxHttpHeaderSize="8192"
maxSpareThreads="75"
maxThreads="256"
minSpareThreads="25"
protocol="HTTP/1.1"
scheme="https"
secure="true"
SSLEnabled="true"
sslProtocol="TLS"
URIEncoding="UTF-8"
acceptCount="100"
SSLCertificateFile="cert.cer"
SSLCertificateKeyFile="cert_key.key
"
/>
------end of snippet----------------------
A quick browse on Google showed up the following discussion:
http://tomcat.10.n6.nabble.com/Managing-Tomcat-6-threads-How-to-make-tomcat-destroy-threads-when-idle-td2114714.html
I might need to change the server.xml to use the executor Thread Pool, I
think.
Thanks.
-Shanti
On Wed, Oct 17, 2012 at 9:07 AM, Pid <p...@pidster.com> wrote:
> On 16/10/2012 17:52, Shanti Suresh wrote:
> > Greetings.
> >
> > I have some questions on finding the number of active threads in Tomcat.
> > (1) On our QA system, I notice that the currenthreadsBusy MBean is
> > either zero or one for the 8443 and 8080 connectors.
>
> ThreadCount != currentThreadsBusy
>
> One is the count of threads, one is the threads that are doing work.
>
>
> > Why then is ThreadCount = 93 when there is not much going on on QA?
>
> Because you've previously done enough work for Tomcat to maintain 93
> threads.
>
>
> > (2) When I want to graph the thread activity in Tomcat (the thread
> > Pool usage), which is a better counter to look at - currentThreadsBusy
> > or "ThreadCount"?
>
> Depends what you want know.
>
>
> > It seems like "ThreadCount" is what JConsole displays as "Live Threads".
> > (3) Why is TotalStartedThreadCount: 264? Is that a cumulative total
> > since Tomcat was restarted?
>
> Yes.
>
>
> p
>
> > --------------Thread-related MBean snippet:---------
> >
> > Name: Catalina:type=ThreadPool,name="http-apr-8443"
> > currentThreadsBusy: 1
> > ...
> >
> > Name: Catalina:type=ThreadPool,name="http-apr-8080"
> > currentThreadsBusy: 0
> > ...
> >
> > Name: java.lang:type=Threading
> > DaemonThreadCount: 85
> > PeakThreadCount: 99
> > AllThreadIds: Array[long] of length 93
> > 135
> > 119
> > 118
> > 117
> > ...
> >
> > CurrentThreadCpuTime: 4600000000
> > CurrentThreadUserTime: 4020000000
> > ThreadCount: 93
> > TotalStartedThreadCount: 264
> > ThreadCpuTimeSupported: true
> > ...
> > ---------------end of snippet------------------------
> >
> > Thanks!
> >
> > -Shanti
> >
>
>
> --
>
> [key:62590808]
>
>
