[pgpool-general: 2738] pgpool passing BEGIN statements to secondaries?

[Christophe Pettus]

Greetings,

We just saw very odd behavior on a client's machine; in particular, pgpool (Ubuntu 12.04, 3.3.2-1.pgdg12.4+1) was passing BEGIN statements and subsequent transactions to the secondary.  We're not sure how that could happen.  The client was connecting via pgbouncer in front of pgpool, using JDBC (driver 9.3-1101-jdbc41).  Example log lines from the secondary attached below.  Thoughts on what might cause this?

postgresql-20140409-222311.csv:2014-04-09 22:23:20.266 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,3,"PARSE",2014-04-09 22:23:20 UTC,29/17505,0,LOG,00000,"duration: 0.183 ms  parse <unnamed>: BEGIN",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.267 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,4,"BIND",2014-04-09 22:23:20 UTC,29/17505,0,LOG,00000,"duration: 0.031 ms  bind <unnamed>: BEGIN",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.269 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,5,"BEGIN",2014-04-09 22:23:20 UTC,29/17505,0,LOG,00000,"duration: 0.032 ms  execute <unnamed>: BEGIN",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.355 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,6,"PARSE",2014-04-09 22:23:20 UTC,29/17505,0,LOG,00000,"duration: 0.047 ms  parse <unnamed>: ROLLBACK",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.358 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,7,"BIND",2014-04-09 22:23:20 UTC,29/17505,0,LOG,00000,"duration: 0.020 ms  bind <unnamed>: ROLLBACK",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.360 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,8,"ROLLBACK",2014-04-09 22:23:20 UTC,29/0,0,LOG,00000,"duration: 0.020 ms  execute <unnamed>: ROLLBACK",,,,,,,,,"db02"
postgresql-20140409-222311.csv:2014-04-09 22:23:20.363 UTC,"db_user","xxx",19545,"172.31.0.232:33043",5345c858.4c59,9,"DISCARD ALL",2014-04-09 22:23:20 UTC,29/0,0,LOG,00000,"duration: 0.129 ms  statement: DISCARD ALL",,,,,,,,,"db02"

--
-- Christophe Pettus
   xof at thebuild.com