On 31.01.2013 06:13, Oskar Zinger wrote: > This is only happening in a specific scenario when a host application > server failbacks, so what it does is stops a service that manages > derby network server, and restarts it.
So, is this an attempt to shut down the ex-slave (now the failed over master) after the old master has been (re)started? I would perhaps be helpful if you can explain the replication scenario in some detail, since replication contains much code specific to replication. Thanks, Dag > > There is no second shutdown, because if that was happening I would see > duplicate debug message that tell me that the code is about to execute > shutdown. > > This is done in master and slave derby replication environment. This > does not happen always during shutdown of derby. > > Thanks, > Oskar > > ------------------------------------------------------------------------ > *From:* Katherine Marsden <[email protected]> > *To:* Derby Discussion <[email protected]> > *Sent:* Wednesday, January 30, 2013 2:16 PM > *Subject:* Re: NullPointerException when Shuting Down Derby > > On 1/30/2013 8:38 AM, Oskar Zinger wrote: >> Hi Kathey, >> >> Here is what happens... >> >> Yes, this is a multi-threaded system. No, only one shutdown request >> is happening. I have not tried with deregister=true. >> >> The new finding is... >> >> This NullPointerException is only happening in a Single CPU (or >> single Core) system. When the system and Kernel is upgraded to 2 CPU >> / core system - the NullPointerException no longer happens, also the >> same has been tried on a 4 CPU / core system and it does not happen >> there again. So strangely this is only happening on a single >> processor system. >> >> I feel that there should be a check for null in >> org.apache.derby.impl.store.raw.xact.XactFactory.add() method to >> check for ttab for null. > > It seems to me that there is something hapenning that we don't > understand. Although I would certainly accept a patch to put a null > check here, my guess is that there might be another NPE that you > will hit down the line if you fix that one, so worth taking a little > time to understand what is going on and try to get a stand alone > reproduction if there is a bug. It has the feel of two shutdowns at > once or maybe some post commit action still happening during the shutdown. > > Can you describe what is going on when this happens and try to make a > reproduction you can post? > I'd say go ahead and file a Jira and put the information there and > attach logs and such for help from the community as you debug. It > would be helpful too to use debug jars so we get line numbers in the > stack trace. > > Best > > Kathey > > > >> >> Regards, >> Oskar >> >> ------------------------------------------------------------------------ >> *From:* Katherine Marsden <[email protected]> >> <mailto:[email protected]> >> *To:* Derby Discussion <[email protected]> >> <mailto:[email protected]> >> *Cc:* Oskar Zinger <[email protected]> <mailto:[email protected]> >> *Sent:* Tuesday, January 29, 2013 12:22 AM >> *Subject:* Re: NullPointerException when Shuting Down Derby >> >> On 1/28/2013 3:04 PM, Oskar Zinger wrote: >>> I just upgraded to 10.8.3 and I am still running into the same >>> NullPointerException (NPE). >>> >>> This is actually different, it comes from: >>> org.apache.derby.impl.store.raw.xact.XactFactory.add(Unknown Source) >>> >> >> Hi Oskar, >> >> Thank you for upgrading to the latest. That always makes things >> easier to debug. >> I guess the next step is to understand how you get into this state. >> Is there a stand alone reproduction that you can post in Jira? >> Is there something in the log prior to this NPE that might give us an >> indication of what was going on when you got the NPE? >> >> Is your program multi-threaded? Is there possibly more than one >> thread shutting down at once? Do you have the same problem if you >> use deregister=true? >> >> >> Best >> >> Kathey >> >> >>> Thanks, >>> Oskar >>> >>> ------------------------------------------------------------------------ >>> *From:* Katherine Marsden <[email protected]> >>> <mailto:[email protected]> >>> *To:* Derby Discussion <[email protected]> >>> <mailto:[email protected]> >>> *Cc:* Oskar Zinger <[email protected]> <mailto:[email protected]> >>> *Sent:* Monday, January 28, 2013 4:28 PM >>> *Subject:* Re: NullPointerException when Shuting Down Derby >>> >>> On 1/28/2013 12:52 PM, Oskar Zinger wrote: >>>> When I do the following it sometimes returns a NullPointerException: >>>> >>>> >>>> DriverManager.getConnection("jdbc:derby:;shutdown=true;deregister=false"); >>>> >>>> Here is the exception stack trace: >>>> >>>> Caused by: java.lang.NullPointerException >>>> at >>>> org.apache.derby.impl.store.raw.xact.XactFactory.add(Unknown Source) >>>> at >>>> org.apache.derby.impl.store.raw.xact.XactFactory.pushTransactionContext(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.store.raw.xact.XactFactory.startInternalTransaction(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.store.raw.log.LogToFile.checkpointWithTran(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.store.raw.log.LogToFile.checkpoint(Unknown >>>> Source) >>>> at org.apache.derby.impl.store.raw.RawStore.stop(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.services.monitor.TopService.stop(Unknown Source) >>>> at >>>> org.apache.derby.impl.services.monitor.TopService.shutdown(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.services.monitor.BaseMonitor.shutdown(Unknown >>>> Source) >>>> at >>>> org.apache.derby.impl.services.monitor.BaseMonitor.shutdown(Unknown >>>> Source) >>>> at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source) >>>> at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown >>>> Source) >>>> at java.sql.DriverManager.getConnection(DriverManager.java:399) >>>> at java.sql.DriverManager.getConnection(DriverManager.java:350) >>>> >>>> Does anyone know why this is happening? >>>> >>>> I am using Derby 10.8.2.3 >>>> >>>> Thanks, >>>> Oskar Zinger >>> >>> https://issues.apache.org/jira/browse/DERBY-5916 was backported to >>> 10.8 with revision 1395186 and looks similar >>> I suggest you pick up 10.8.3 that has that fix. >>> >>> >>> >> >> >> > > >
