Re: Pipelining executions to postgresql server

On 11/01/2014 10:04 PM, Mikko Tiihonen wrote:
> Hi,
>
> I created a proof of concecpt patch for postgresql JDBC driver that allows the caller to do pipelining of requests
withina transaction. The pipelining here means same as for HTTP: the client can send the next execution already before
waitingfor the response of the previous request to be fully processed. 

... but ... it already does that.

Use batches, and that's exactly what it'll do.

Statement.addBatch(String)
or
PreparedStatement.addBatch()

> What kind of problems could pipelining cause (assuming we limit it to rather simple use cases only)?

Client/server pipleline deadlocks due to how PgJDBC manages it.

See the details:

https://github.com/pgjdbc/pgjdbc/issues/195

and

https://github.com/pgjdbc/pgjdbc/issues/194

--
 Craig Ringer                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services