On Tue, Jan 3, 2017 at 3:32 PM, Ashutosh Bapat <ashutosh.ba...@enterprisedb.com> wrote: > I am wondering what happens if a 2PC file gets created, at the time of > checkpoint we flush the pg_twophase directory, then the file gets > removed. Do we need to flush the directory to ensure that the removal > persists? Whatever material I look for fsync() on directory, it gives > examples of file creation, not that of deleting a file. If we want to > persist the removal, probably we have to flush pg_twophase always or > add code to track whether any activity happened in pg_twophase between > two checkpoints. The later seems complication not worth the benefit.
There is already the delay checkpoint machinery to cover timing problems here. Have a look for example at EndPrepare()@twophase.c. > I guess, it's hard to construct a case to reproduce the issue > described in your first mail. But still checking if you have any > reproduction. May be we could use similar reproduction to test the > deletion of two phase file. Not really. You can just do the test on a VM (one transaction generating a 2PC file, followed by a checkpoint), then kill-9 its parent instance. That's radical to emulate the power loss. I do that on macos with VMware Fusion. -- Michael -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers