Weblogic.utils.StackTraceUtils not found

Question

Platform: Sun OS 5.7 (Solaris 2.7?), Weblogic 5.1 SP6.
          I have an application that contains some JSPs and Servlets. I'm using
          SilkPerformer to simulate multiple users. It was fine if I used only 200
          virtual users, but I ran into the following problem when I used 250 (240
          too).
          It complained some kind of NullPointerException (see below) which never
          happened for under 200 users. And then it complained this
          weblogic.utils.StackTraceUtils not found. This class belongs to
          /weblogic/classes which is in my weblogic.class.path when the server is
          started.
          I'm guess weblogic server ran into some unexpected exception and the
          logger wanted to call this class to report the error. So I need to find
          out 2 things:
          1. how to reveal the real exception/error.
          2. what to do to avoid the exception (since it worked fine for 200
          virtual users).
          For 1, I have no clue. Hope someone out there can help me.
          For 2, I remember seeing "Too many opened files" at some run which may
          indicating that, when handling too many users (250) at one time, WL
          server has opened one copy of certain file (JSP/html) for each user and
          used up system allowed file handles. If this is true, I may be able to
          get rid of this problem by increasing the allowed number of file
          handles. But I'd like to see a better solution (say, configure the
          server certain way to share the files). By the way, this is not
          happening on NT. Maybe NT has more allowed file handles and I can only
          run as many as 250 users.
          Anyway comments are appreciated.
          -Wayne
          ----------------------- extract of server output --------------------
          The errorIndices is currently: []
          Hints validated.java.lang.NullPointerException
          at weblogic.boot.ServerClassLoader.findLocalClass(Compiled
          Code)
          at weblogic.boot.ServerClassLoader.loadClass(Compiled Code)
          at java.lang.ClassLoader.loadClass(Compiled Code)
          at java.lang.ClassLoader.loadClassInternal(Compiled Code)
          at
          weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          at weblogic.logging.LogManager.log(Compiled Code)
          at weblogic.logging.LogOutputStream.error(Compiled Code)
          at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          java.lang.NullPointerException
          at weblogic.boot.ServerClassLoader.findLocalClass(Compiled
          Code)
          at weblogic.boot.ServerClassLoader.loadClass(Compiled Code)
          at java.lang.ClassLoader.loadClass(Compiled Code)
          at java.lang.ClassLoader.loadClassInternal(Compiled Code)
          at
          weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          at weblogic.logging.LogManager.log(Compiled Code)
          at weblogic.logging.LogOutputStream.alert(Compiled Code)
          at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          Wed Nov 22 15:25:09 MST 2000:<!> <ListenThread> **** The WebLogic Server
          is n\
          o longer listening for connections.
          Wed Nov 22 15:25:09 MST 2000:<!> <ListenThread> **** You should probably
          rest\
          art it.
          Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown by
          system
          Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown
          commencing \
          NOW
          Wed Nov 22 15:25:09 MST 2000:<A> <SSLListenThread> ListenThread.run()
          failed:\
          java.lang.ThreadDeath
          Wed Nov 22 15:25:09 MST 2000:<!> <SSLListenThread> **** The WebLogic
          Server i\
          s no longer listening for connections.
          Wed Nov 22 15:25:09 MST 2000:<!> <SSLListenThread> **** You should
          probably r\
          estart it.
          Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown by
          system
          java.lang.NoClassDefFoundError: weblogic/utils/StackTraceUtils
          at
          weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          at weblogic.logging.LogManager.log(Compiled Code)
          at weblogic.logging.LogOutputStream.alert(Compiled Code)
          at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          hints are: [Ljava.lang.String;@1646d1e
          hints are: [Ljava.lang.String;@ef3ad1
          hints are: [Ljava.lang.String;@a43826
          

Answer 1

Thanks Sumanth and Cameron. I have 64 descriptors when I do "limit". I'm
          not sure if that's my limit coz I could successfully simulate 200 users
          at a time. I only have a few JSPs and a couple of HTMLs. Maybe Weblogic
          is already sharing the files. Or maybe even for 200 users, at one time
          no more than 64 descriptors are used.
          I don't have super-user privileges. But I'll ask the admins to increase
          the limit for me and see how that affects my results.
          Appreciate your help.
          -Wayne
          Sumanth Yamala wrote:
          >
          > lsof gives the number of file descriptors open
          >
          > A common setting for high-load systems is a soft limit of 1024 and a hard
          > limit of 4096.
          >
          > On Solaris, add the following to /etc/system:
          >
          > set rlim_fd_max=4096
          > set rlim_fd_cur=1024
          >
          > And reboot with -r.
          >
          > You should not raise it past 1024 without first finding some
          > documentation that confirms that it is safe to do so. Any number
          > below that is safe.
          >
          > To add to the above Weblogic documentation has to say this:
          >
          > We have seen this situation when the user account runs out of file
          > descriptors. On Solaris, each user account has a certain limited number of
          > file descriptors. You can find out how many file descriptors you have with
          > the limit command in csh.
          >
          > You can increase file descriptors if you have enough privileges with the
          > unlimit command in the csh. Otherwise, you'll need to ask your system
          > administrator to increase the file descriptors available to your processes.
          >
          > Another solution is to create a .zip file with all of the WebLogic classes,
          > since a .zip file only requires a single file descriptor. If you do this,
          > please note that there may be other problems associated with loading files
          > from a .zip file, particularly with versions of the JDK before 1.1.3.
          > (Previous to version 2.5, WebLogic has not distributed its classes in .zip
          > format because of limitations in the JVM
          >
          > -Sumanth
          >
          > Wayne Xin wrote:
          >
          > > Platform: Sun OS 5.7 (Solaris 2.7?), Weblogic 5.1 SP6.
          > >
          > > I have an application that contains some JSPs and Servlets. I'm using
          > > SilkPerformer to simulate multiple users. It was fine if I used only 200
          > > virtual users, but I ran into the following problem when I used 250 (240
          > > too).
          > >
          > > It complained some kind of NullPointerException (see below) which never
          > > happened for under 200 users. And then it complained this
          > > weblogic.utils.StackTraceUtils not found. This class belongs to
          > > /weblogic/classes which is in my weblogic.class.path when the server is
          > > started.
          > >
          > > I'm guess weblogic server ran into some unexpected exception and the
          > > logger wanted to call this class to report the error. So I need to find
          > > out 2 things:
          > >
          > > 1. how to reveal the real exception/error.
          > > 2. what to do to avoid the exception (since it worked fine for 200
          > > virtual users).
          > >
          > > For 1, I have no clue. Hope someone out there can help me.
          > >
          > > For 2, I remember seeing "Too many opened files" at some run which may
          > > indicating that, when handling too many users (250) at one time, WL
          > > server has opened one copy of certain file (JSP/html) for each user and
          > > used up system allowed file handles. If this is true, I may be able to
          > > get rid of this problem by increasing the allowed number of file
          > > handles. But I'd like to see a better solution (say, configure the
          > > server certain way to share the files). By the way, this is not
          > > happening on NT. Maybe NT has more allowed file handles and I can only
          > > run as many as 250 users.
          > >
          > > Anyway comments are appreciated.
          > >
          > > -Wayne
          > >
          > > ----------------------- extract of server output --------------------
          > > ...
          > > The errorIndices is currently: []
          > > Hints validated.java.lang.NullPointerException
          > > at weblogic.boot.ServerClassLoader.findLocalClass(Compiled
          > > Code)
          > > at weblogic.boot.ServerClassLoader.loadClass(Compiled Code)
          > > at java.lang.ClassLoader.loadClass(Compiled Code)
          > > at java.lang.ClassLoader.loadClassInternal(Compiled Code)
          > > at
          > > weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          > > at weblogic.logging.LogManager.log(Compiled Code)
          > > at weblogic.logging.LogOutputStream.error(Compiled Code)
          > > at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          > > java.lang.NullPointerException
          > > at weblogic.boot.ServerClassLoader.findLocalClass(Compiled
          > > Code)
          > > at weblogic.boot.ServerClassLoader.loadClass(Compiled Code)
          > > at java.lang.ClassLoader.loadClass(Compiled Code)
          > > at java.lang.ClassLoader.loadClassInternal(Compiled Code)
          > > at
          > > weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          > > at weblogic.logging.LogManager.log(Compiled Code)
          > > at weblogic.logging.LogOutputStream.alert(Compiled Code)
          > > at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          > > Wed Nov 22 15:25:09 MST 2000:<!> <ListenThread> **** The WebLogic Server
          > > is n\
          > > o longer listening for connections.
          > > Wed Nov 22 15:25:09 MST 2000:<!> <ListenThread> **** You should probably
          > > rest\
          > > art it.
          > > Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown by
          > > system
          > > Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown
          > > commencing \
          > > NOW
          > > Wed Nov 22 15:25:09 MST 2000:<A> <SSLListenThread> ListenThread.run()
          > > failed:\
          > >
          > > java.lang.ThreadDeath
          > >
          > > Wed Nov 22 15:25:09 MST 2000:<!> <SSLListenThread> **** The WebLogic
          > > Server i\
          > > s no longer listening for connections.
          > > Wed Nov 22 15:25:09 MST 2000:<!> <SSLListenThread> **** You should
          > > probably r\
          > > estart it.
          > > Wed Nov 22 15:25:09 MST 2000:<I> <WebLogicServer> Server shutdown by
          > > system
          > > java.lang.NoClassDefFoundError: weblogic/utils/StackTraceUtils
          > > at
          > > weblogic.logging.TextStreamLogger.log(TextStreamLogger.java:77)
          > > at weblogic.logging.LogManager.log(Compiled Code)
          > > at weblogic.logging.LogOutputStream.alert(Compiled Code)
          > > at weblogic.t3.srvr.ListenThread.run(Compiled Code)
          > > hints are: [Ljava.lang.String;@1646d1e
          > > hints are: [Ljava.lang.String;@ef3ad1
          > > hints are: [Ljava.lang.String;@a43826
          > > ....