Max threads allocating limit problem in HP-UX.

How much threads can be allocated in HP-UX?

Can HP-UX limit threads allocating count per user?

I am running Tomcat on HP-UX, I offten catch this Excption

$ cat logs/catalina.out | grep OutOfMemory
Caught exception (java.lang.OutOfMemoryError: unable to create new native
thread) executing org.apache.tomcat.util.net.TcpWorkerThread@1c20611 ,
terminating thread


the command tomcat running is as following:

java -Xms64m -Xmx320m -Xss2m -Djava.awt.headless=true -Djava.endorsed.dirs=/dlsapp/jakarta-tomcat-5.0.28/common/endorsed
-classpath
/dlsapp/jdk142_05/lib/tools.jar:/dlsapp/jakarta-tomcat-5.0.28/bin/bootstrap.jar:/dlsapp/jakarta-tomcat-5.0.28/bin/commons-logging-api.jar
-Dcatalina.base=/dlsapp/jakarta-tomcat-5.0.28 -Dcatalina.home=/dlsapp/jakarta-tomcat-5.0.28
-Djava.io.tmpdir=/dlsapp/jakarta-tomcat-5.0.28/temp
org.apache.catalina.startup.Bootstrap start

The server.xml of tomcat is:

<!--
Threads allocated by tomcat is 16, max is 128, max spare is 64.
128 sames quite a small count. -__-#
-->
<Connector port="8080"
maxThreads="128" minSpareThreads="16" maxSpareThreads="64"
enableLookups="false" redirectPort="8443" acceptCount="100"
debug="0" connectionTimeout="1800"
disableUploadTimeout="true" />


I hove no root privilege on this machine...

Thank you

I think I got it.

I contact the administrator, The max count of thread per process is 64. but
Tomcat only have one process, so the tomcat can't reach 128 and throw
exception.

How many threads per process can be set? administrator will set it to 256.
Is it big enough?

"Aray" <1@2.3> дÈëÏûÏ¢ÐÂÎÅ:dovkhh$j4q$1@news.cn99.com...
> How much threads can be allocated in HP-UX?

Aray wrote:
> I think I got it.
>
> I contact the administrator, The max count of thread per process is 64. but
> Tomcat only have one process, so the tomcat can't reach 128 and throw
> exception.
>
> How many threads per process can be set? administrator will set it to 256.
> Is it big enough?
>
> "Aray" <1@2.3> дÈëÏûÏ¢ÐÂÎÅ:dovkhh$j4q$1@news.cn99.com...
>
>>How much threads can be allocated in HP-UX?
>
>
>
Have the admin look at nkthreads and max_thread_proc, both static kernel
tunables.

"Alan D Johnson" <adjtech@hvc.rr.com>
??????:K6Xsf.22158$Ed.16693@news-wrt-01.rdc-nyc.rr.com...
> Have the admin look at nkthreads and max_thread_proc, both static kernel
> tunables.

Thanks for replay.

I konw little about HP-UX, I saw the max_thread_proc on admin's screen, it
was 64. didn't see nkthreads

I should read some document befor diving here,

Aray wrote:
> "Alan D Johnson" <adjtech@hvc.rr.com>
> ??????:K6Xsf.22158$Ed.16693@news-wrt-01.rdc-nyc.rr.com...
>
>>Have the admin look at nkthreads and max_thread_proc, both static kernel
>>tunables.
>
>
> Thanks for replay.
>
> I konw little about HP-UX, I saw the max_thread_proc on admin's screen, it
> was 64. didn't see nkthreads
>
> I should read some document befor diving here,
>
>

Hi,

kmtune or kctune give a listing of kernel parameters and their values.

See http://docs.hp.com/en/939/KCParms/KC...erviewAll.html for a full listing with detailled explanations.

max_thread_proc: maximum number of threads that one process can create
nkthread: maximum number of kernel threads allowed on the system at same time

Default kernel values are generaly far too low (however too high is not recommended) for java programming under hpux 11.11
I recommend to install free HP product "Java Out-of-Box tool for HP-UX 11i "
http://www.hp.com/products1/unix/java/?jumpid=go/java

See also doc "Common Misconfigured HP-UX Resources" http://docs.hp.com/en/5580/Misconfigured_Resources.pdf
With "gpm" (glance), you can see how many threads a process has.

A good setup of kernel parameters protect OS from runaway processes while allowing programs to run without annoying limitations.


Alain.

Thanks a lot, I think all of these operations need Root privilege. But I
have no root account...

"toto" <ota1998@hotmail.com>
??????:43b648e3$0$19880$ba620e4c@news.skynet.be...

> kmtune or kctune give a listing of kernel parameters and their values.
>
> See http://docs.hp.com/en/939/KCParms/KC...erviewAll.html for a full
> listing with detailled explanations.
>