For single thread, consistency ALL it should work. I believe you do something different. What are these three numbers exactly? old=60616 val =19 new =60635
On Fri, Jan 10, 2014 at 1:50 PM, Manoj Khangaonkar <khangaon...@gmail.com>wrote: > Hi > > Using Cassandra 2.0.0. > 3 node cluster > Replication 2. > Using consistency ALL for both read and writes. > > I have a single thread that reads a value, updates it and writes it back > to the table. The column type is big int. Updating counts for a timestamp. > > With single thread and consistency ALL , I expect no lost updates. But as > seem from my application log below, > > 10 07:01:58,507 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=59614 val =252 new =59866 > 10 07:01:58,611 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=59866 val =252 new =60118 > 10 07:01:59,136 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=60118 val =255 new =60373 > 10 07:02:00,242 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=60373 val =243 new =60616 > 10 07:02:00,244 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=60616 val =19 new =60635 > 10 07:02:00,326 [Thread-10] BeaconCountersCAS2DAO [INFO] 1389366000 H > old=60616 val =233 new =60849 > > See the last 2 lines of above log. > value 60116 is updated to 60635. but the next operation reads the old > value 60616 again. > > I am not using counter column type because it does not support TTL and i > hear there are lot of open issues with counters. > > Is there anything else I can do to further tighten the consistency or is > this pattern of high volume read - update - write not going to work in C* ? > > regards > MJ > > -- > >
