Re: [bdbxml] General questions regarding transactions et al

George Feinberg <gmf@...> writes:

> 
> 
> The fact that you are getting DB_LOCK_NOTGRANTED
> implies that you've set some configuration asking
> for either a lock timeout or set DB_LOCK_NOWAIT.
> 
> What configuration options are you using for your
> Environment?
> 
> Do you really need to be using transactions in the first place?
> If you don't need them, you can simplify things.
> 
> The error, DB_LOCK_NOTGRANTED will occur when
> the system would otherwise deadlock.  This means
> that when you perform your updateDocument() call,
> some thread (perhaps the current one) is holding
> locks that are required for the update to happen.
> 
> A possible cause is not committing a transaction, or
> mixing (by accident) transactional and non-transactional
> operations.
> 
> Regards,
> 
> George
> 
> > I'm still trying to get my app running, but the DB_LOCK_NOTGRANTED- 
> > error
> > remains. Here's what the console's up to when I start the program:
> >
> > Updating documents
> > Found 1 matching the expression   <--check, if file's present
> > Updating document:
> > Updating with new document        <--if so, update the document in  
> > the container
> >
> > ---ENVIRONMENT DETAILS------     <-- some environment & transaction  
> > stuff
> > max lockers: 100000
> > deadlock detection value: 0
> > reg size: 98304
> > stats (last) id: 964
> > curmaxid id: 2147483647
> > ---TRANSACTION DETAILS------
> > transaction commits: 13
> > max transactions (getMaxTxns()): 20
> > last transaction id: -2147483634
> > no. of aborted transactions: 0
> > no. of active transactions: 1
> > reg size (getRegSize()): 16384
> > max active transactions(getMaNactive()): 2
> >
> > Error performing document update against mainDataStorage.dbxml
> >    Message: Error: Db::del: DB_LOCK_NOTGRANTED: Lock not granted
> > Exception in thread "main" com.sleepycat.dbxml.XmlException: Error:  
> > Db::del:
> > DB_LOCK_NOTGRANTED: Lock not granted, errcode = DATABASE_ERROR
> >     at  
> > com.sleepycat.dbxml.dbxml_javaJNI.XmlContainer_updateDocument__SWIG_1( 
> > Native
> > Method)
> >     at com.sleepycat.dbxml.XmlContainer.updateDocument 
> > (XmlContainer.java:361)
> >     at ws.updateFile.doUpdateDocument(updateFile.java:109)
> >     at ws.updateFile.updateDocument(updateFile.java:247)
> >     at ws.updateFile.main(updateFile.java:275)
> >
> > Are there some general issues I should be aware of? I really don't  
> > get it. Does
> > "max transactions" really have anything to do with the transactions  
> > committed?
> > If so, why should the actual stat be a problem? I've used to work  
> > with sql data
> > bases so this whole problem's just confusing me, stabbing around in  
> > the darkness
> > of transactional void. What would be the best approach to solve the  
> > problem? Any
> > clever way of debugging faulty (berkeley db xml) database actions?
> >
> > Thnx in advance,
> >
> > M.B.
> 
> ------------------------------------------
> To remove yourself from this list, send an
> email to xml-unsubscribe@...
> 
> 


Hi, thank you for your fast response. 

The environment configuration's like this:

config.setAllowCreate(true);
	    	    config.setInitializeCache(true);
	    	    config.setCacheSize(60 * 1024 * 1024);
	    	    config.setTransactional(true);
	    	    config.setInitializeLocking(true);
	    	    config.setLockTimeout(100); //TimeOut-Zeit in Millisekunden
	    	    config.setMaxLocks(10000);
	    	    config.setMaxLockers(100000);
	    	    config.setMaxLockObjects(10000);
	    	    config.setLockDetectMode(LockDetectMode.EXPIRE);
	    	    config.setInitializeLogging(true);
	    	    config.setLogAutoRemove(true);
	    	    config.setErrorStream(System.err);
	    	    config.setInitializeRegions(true);
	    	    config.setInitializeReplication(false);
	    	    config.setThreaded(true);
	    	    config.setTxnTimeout(1000); 


I don't know if I need transactions, thinking about, probably not, since my
little app will never be used in some critical application environment. Just
exploring new ways here. What other options can I chose from? Maybe working with
XmlModify instead? 

Kind regards,

M.B.



------------------------------------------
To remove yourself from this list, send an
email to [email protected]