Hi 2016-03-10 19:55 GMT+01:00 Robert Haas <[email protected]>:
> Provide much better wait information in pg_stat_activity. > > When a process is waiting for a heavyweight lock, we will now indicate > the type of heavyweight lock for which it is waiting. Also, you can > now see when a process is waiting for a lightweight lock - in which > case we will indicate the individual lock name or the tranche, as > appropriate - or for a buffer pin. > > Amit Kapila, Ildus Kurbangaliev, reviewed by me. Lots of helpful > discussion and suggestions by many others, including Alexander > Korotkov, Vladimir Borodin, and many others. > > Branch > ------ > master > > I am trying to test this feature, and there I see not actual data. Maybe this behave is not related to this patch: create table foo(a int); insert into foo values(10); session one: begin; select * from foo for update; session two: begin; select * from foo for update; session two is waiting session one: select * from pg_stat_activity -- I don't see correct information about session two session two: rollback; begin; select * from foo where a = 10 for update; session two is waiting again session one: select * from pg_stat_activity; -- The content is not changed So content of pg_stat_activity is not correct in holder lock session. Independent third session see valid content of pg_stat_activity. Hypothesis: the pg_stat_activity is not refreshed under opened transaction? Regards Pavel
