Re: ReplicationConnection and wait_timeout
Posted by: vladkravchenko
Date: June 19, 2007 10:53AM

Hi,

I have the same issue.
Have you found any solution?

I have tried it with driver version 5.0.6.
I guess the driver sends some packets to master db even for readOnly connections, like:
191 Query USE `test`
191 Query SELECT @@session.tx_isolation
191 Query SET autocommit=1


In this case each read access creates additional load on the master and the whole system doesn't scale well.

If I add useLocalSessionState=true property to the connection string, readonly requests don't affect master, but I am getting problem with connections closed by MySQL after wait_timeout.

The solution could be to extend BasicDataSource and send validation query twice, once with connection.setReadonly(true) and one with false. Doing it in onBorrow would add to much load. But having a background thread sending validation query once a minute for all idle connections could help.

Any thoughts?

/Vlad

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Re: ReplicationConnection and wait_timeout
June 19, 2007 10:53AM


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