It seems the problem is with MVCC.

The test is not failing for 30s on my system with: "jdbc:h2:db/test01;MVCC=*
FALSE*;MULTI_THREADED=0;LOCK_MODE=3;LOCK_TIMEOUT=20000;"

All isolation levels fail for (in the 1-5s 
timeframe): "jdbc:h2:db/test01;MVCC=*TRUE;*
MULTI_THREADED=0;LOCK_MODE=3;LOCK_TIMEOUT=20000;" 
Connection.TRANSACTION_READ_UNCOMMITTED
Connection.TRANSACTION_READ_COMMITTED
Connection.TRANSACTION_REPEATABLE_READ
Connection.TRANSACTION_SERIALIZABLE

On Tuesday, December 4, 2012 11:01:37 AM U
TC+2, Noel Grandin wrote:
>
> Hmmm, I think what is happening here is that when in MVCC mode with 
> transaction isolation level TRANSACTION_READ_COMMITTED, the session is 
> somehow seeing LOB entries that have already been deleted. 
>
> Thomas, does that ring any bells? 
>
> I've been through the code paths that end up in LobStorage, but I can't 
> see any obvious problems. 
>
> On 2012-12-03 09:58, Noel Grandin wrote: 
> > Nice work on creating the test case! 
> > 
> > Interesting, this is a genuine bug somewhere in the LOB code, and it 
> > manifests even with MVCC=false. 
> > 
> > The only short-term fix I can see is to set your transaction isolation 
> > to  TRANSACTION_REPEATABLE_READ. 
> > 
> > Thomas, I further reduced the test-case, and I'm including it here. 
> > Note that (for me) it did not fail every single time. I normally let 
> > it run for about 15 seconds, and then terminate and try again. 
> > I get a failure rate of about 50%. 
> > 
>
>

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