tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Rainer Jung <rainer.j...@kippdata.de>
Subject Re: What is default value of CATALINA_OPTS at apache-tomcat-6.0.29?
Date Thu, 02 Sep 2010 09:12:08 GMT
On 02.09.2010 07:12, takanobu watanabe wrote:
> Hello Rainer,
>
> Thanks detailed explain.
> and now I use jconsole to measuring.
> But when jconsole try to connect remote target host, JVM down.
> Probably it is not tomcat issue,I think.

Yeah, looks like a JVM issue. If you file a bug there, provide the 
contents of the hotspot error file (/root/hs_err_pid1696.log) to those 
people.

Regards,

Rainer

> I may close this issue.
> Regard,
>
> --catalina.out--
> ...
> #
> # An unexpected error has been detected by Java Runtime Environment:
> #
> #  Internal Error (os_linux_zero.cpp:157), pid=1696, tid=1735849104
> #  Error: caught unhandled signal 11
> #
> # Java VM: OpenJDK Core VM (1.6.0_0-b11 interpreted mode linux-arm)
> # An error report file with more information is saved as:
> # /root/hs_err_pid1696.log
> #
> # If you would like to submit a bug report, please visit:
> #   http://icedtea.classpath.org/bugzilla
> # The crash happened outside the Java Virtual Machine in native code.
> # See problematic frame for where to report the bug.
> ---
>
> On 31 August 2010 20:57, Rainer Jung<rainer.jung@kippdata.de>  wrote:
>> On 31.08.2010 13:14, takanobu watanabe wrote:
>>>
>>> Thank you very much Rainer.
>>>
>>>> Tomcat itself doesn't need much memory and you should be able to run it
>>>> with less than 64MB Heap (plus Perm)
>>>
>>> I recognized 64MB>=  Am +  Bm from your advice.
>>> Is my recognized correct ?
>>> ---example catalina.sh---
>>> -XX:NewSize=Am -XX:MaxNewSize=Am
>>>   -XX:PermSize=Bm -XX:MaxPermSize=Bm"
>>
>> I don't actually understand the question, but here's the terminology (I hope
>> the picture isn't disturbed by line breaks):
>>
>> <---------------------- Heap -------------------><- Perm ->
>> <----------------- New ----------------><- Old ->
>> <- Eden -><- Survivor1 -><- Survivor2 ->
>>
>> Sometimes New is also defined as Eden plus one of the two survivors,
>> especially in the verbose GC output.
>>
>> The two survivors are also called "From Space" and "To Space", the roles
>> change during each GC run in New.
>>
>> Xms, Xmx: minimum and maximum heap size
>> XX:NewSize, XX:MaxNewSize: minimum and maximum size of New
>> XX:PermSize and XX:MaxPermSize: minimum and maximum size of Perm
>>
>> Sizes of Survivor spaces (each one) are determined by
>>
>> Size of Survivor = Size of New / (SurvivorRatio + 2)
>>
>> So if SurvivorRatio is some number N, then the Ratios are
>>
>> Eden:Survivor1:Survivor2 = N:1:1
>>
>> and New = (N+2) * One Survivor
>>
>> Regards,
>>
>> Rainer
>>
>>> On 31 August 2010 19:00, Rainer Jung<rainer.jung@kippdata.de>    wrote:
>>>>
>>>> On 31.08.2010 10:34, takanobu watanabe wrote:
>>>>>
>>>>> Hello,
>>>>>
>>>>> What is default value of CATALINA_OPTS at apache-tomcat-6.0.29 ?
>>>>> It means No configure catalina.sh as same as value of CATALINA_OPTS
>>>>> just expand tomcat.
>>>>>
>>>>> Because I try to run tomcat lean physical memory condition(128Mb only
>>>>> with armv5).
>>>>> When nothing configure to catalina.sh(default),Tomcat works well.
>>>>> But when I configure below,looks like always FullGC running and could
>>>>> not access WEB service.
>>>>> ---
>>>>> CATALINA_OPTS=" -verbose:gc -XX:+PrintGCTimeStamps -Xms64m -Xmx64m
>>>>> -XX:NewSize=32m -XX:MaxNewSize=32m
>>>>> -XX:SurvivorRatio=2 -XX:PermSize=16m -XX:MaxPermSize=16m"
>>>>> ---
>>>>> If anyone has idea or suggest of run tomcat on lean physical memory
>>>>> condition, I would like to know.
>>>>
>>>> If you don't add explicit memory options, the default memory sizes of
>>>> your
>>>> JVM are used. Those might depend on the exact jvm version and also on the
>>>> type of system you run it on (total memory, CPUs).
>>>>
>>>> The easiest way to find out the sizes for your jvm are running it without
>>>> explicit settings and then measuring it. Measuring can be done with tools
>>>> like jstat, jconsole or jvisualvm, or you can add a few verbose gc flags
>>>> to
>>>> print out the sizes of the different memory regions during each run of
>>>> the
>>>> GC, e.g.
>>>>
>>>> -verbose:gc -XX:+PrintGCDetails -XX:+PrintHeapAtGC -XX:+PrintGCTimeStamps
>>>>
>>>> Note that the default settings will allow some of the regions to grow and
>>>> shrink, so you need to make observations for a longer time to find out
>>>> the
>>>> values which are effective most of the time.
>>>>
>>>> I expect your above settings might not leave enough room in the Old
>>>> Generation (aka Tenured), because your New Generation is somwhat large
>>>> relative to the Old Gen. Tomcat itself doesn't need much memory and you
>>>> should be able to run it with less than 64MB Heap (plus Perm), but what
>>>> you
>>>> need in the end depends on the application inside (and the concurrency
>>>> induced by the load). I never experimented to find a minimum value
>>>> though.
>>>>
>>>> Regards,
>>>>
>>>> Rainer

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


Mime
View raw message