[Wrapper-user] RE: Other Processes affecting Servicewrapper

[Ramachandra, A. <Ram...@Sy...>]

Hi Leif
         I found we are using version 2.9.
Let me upgrade to the latest and give it a shot.
 
I was getting a message like this:
 
INFO   | wrapper  | 2003/05/08 10:15:28 | Wrapper Process has not received
any CPU time for 36 seconds.  Extending timeouts.
ERROR  | wrapper  | 2003/05/08 10:15:28 | JVM exited unexpectedly.
STATUS | wrapper  | 2003/05/08 10:15:35 | Launching a JVM...
 
 -Thanks
 -Arun

-----Original Message-----
From: Leif Mortenson [mailto:le...@ta...]
Sent: Thursday, May 08, 2003 12:00 PM
To: Arun Ramachandra
Cc: Ryan Shaw; Wrapper User List
Subject: Re: Other Processes affecting Servicewrapper


Arun,
    What version of the Wrapper are you using?  Newer versions of the
Wrapper are able to detect that the CPU is at 100%.  Rather than timing
out and restarting the JVM, you will get a message like the following:

jvm 1    | JVM Process has not received any CPU time for 11798 seconds.
Extending timeouts.
wrapper  | Wrapper Process has not received any CPU time for 11800 seconds.
Extending timeouts.

    The case above was when I had suspended my system for a few hours.
The Wrapper was able to recover without any problems.  The warning message
is just that, a warning.   If another process takes up 100% of the CPU you
may see one or both of the above messages.  But hopefully it would be for
a period of time much shorter than the 3 hours above. :-)

    Were you seeing timeouts and JVM restarts or had you just noticed the
note in Troubleshooting guide?  I'll take a look at that entry and bring it
up
to date.

Cheers,
Leif

Ryan Shaw wrote:


On Thu, 2003-05-08 at 22:34, Arun Ramachandra wrote:



  

I have seen in the Troubleshooting section of your website the 

following line:



"the Wrapper will think that the JVM is hung when it isn't if 

another process is taking 100% of the CPU for longer than 30 

seconds. This will result in an entry like the following in your 

log file, and the JVM being restarted:"



My question is why is my process being penalised if the 

other process is taking up 100% of cpu time?

Secondly is there some way to avoid this?

    



If another process is taking 100% of CPU, then there is no

CPU left for the JVM. The wrapper has no way of knowing that 

the reason the JVM has not pinged it is that the JVM is being 

starved of processor power. So, it makes the assumption that 

the JVM has hung.



The only way to avoid this is to not let other processes 

dominate your server for long periods. If you are running

on unix you could use "nice" to achieve this.