Data loss with H2 HA / Clustered Mode
Hi, We are trying to use the H2 DB after switching from Apache Derby. This main reason for this was because of the clustering support in H2. After a fair amount of testing we have now come across a problem with the clustered mode. I have configured a system to use H2 (1.3.172) in clustered mode and access the DB using the supplied connection pool. Our application has many threads accessing the DB concurrently (from Web Services and background tasks). The main purpose of the DB is to hold a job queue where the job is added to the table, updated frequently while active and then set to complete. I have found when the system is under load job records can “disappear” from the DB (many jobs being submitted and updates to existing records, ~40 out of 1000 jobs lost). This doesn’t happen when the DB is run in standalone mode. I don’t know how the clustering mode works internally but I was wondering if the transactions are not making it to one of the DB instances but this instance is then used for reading. Would this be possible? Could it be something I have set-up incorrectly? Does clustering work OK with the connection pool class? We had to switch to sequences for id generation, could I have done something wrong there? Any help would be much appreciated. I am happy to supply more details if required. Regards, Daniel Stone -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/groups/opt_out.
