On 2016-04-28 17:41:29 +0100, Thom Brown wrote: > I've noticed another breakage, which I can reproduce consistently.
> 2016-04-28 17:36:08 BST [18108]: [47-1] user=,db=,client= DEBUG: could not > fsync file "base/24581/24594.1" but retrying: No such file or directory > 2016-04-28 17:36:08 BST [18108]: [48-1] user=,db=,client= ERROR: could not > fsync file "base/24581/24594.1": No such file or directory > 2016-04-28 17:36:08 BST [18605]: [17-1] > user=thom,db=postgres,client=[local] ERROR: checkpoint request failed > 2016-04-28 17:36:08 BST [18605]: [18-1] > user=thom,db=postgres,client=[local] HINT: Consult recent messages in the > server log for details. Yuck. md.c is so crummy :( Basically the reason for the problem is that mdsync() needs to access "formally non-existant segments" (as in ones where previous segments are < RELSEG_SIZE), because we queue (and the might be preexistant) fsync requests via register_dirty_segment() in mdtruncate(). I'm a bit of a loss of how to reconcile that view with the original issue in this thread. The best I can come up with this moment is doing a _mdfd_openseg() in mdsync() to open the truncated segment if _mdfd_getseg() returned NULL. We don't want to normally use that in either function because it'll imply a separate open() etc, which is pretty expensive - but doing in the fallback case would be kind of ok. Andres -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers