Degradation of performance when upgrade psqlodbc to 09.03.0400

Hi,

I'm using psqlodbc version 09.00.0310 for my project. Recently i tried to upgrade to version 09.03.0400 and found that it is very slow in processing my batch (batch with milion of SELECT, UPDATE, INSERT statements).

[environment]

OS: Redhat 6.7 x 2 nodes

PostgreSQL 9.1.19: Synchronouse Streaming replication & hot_standby.

DB connect method: psqlodbc/unixODBC.

[results of performance]

It took below timing to execute my batch

In version 09.00.0310: 11minute

In version 09.03.0400: 53minute

When my batch run in 09.03.0400, ps command repeatedly show below processes.

Something delay the transmitting & replaying WAL in STANDBY db node?

-----

... UPDATE waiting for 0/xxx

or

... INSERT waiting for 0/yyy

------

Note that, my replication connection is working well, and above messages just display within a second. This phenomenon is not reproduced in version 09.00.0310.

I have confirmed release note. I thought changing of UseServerSidePrepare's default value made this perfomance problem but not. I don't know what change make it slower.

Sorry for lack of infomation but, is any big changes related to performance between above versions?

Best regards,
bocap.