On Sunday 14 February 2010 21:57:08 Robert Haas wrote: > On Sun, Feb 14, 2010 at 10:31 AM, Greg Stark <gsst...@mit.edu> wrote: > > On Sun, Feb 14, 2010 at 2:03 PM, Greg Stark <gsst...@mit.edu> wrote: > >> On Fri, Feb 12, 2010 at 3:49 PM, Robert Haas <robertmh...@gmail.com> wrote: > >>> Greg Stark, have you managed to get your access issues sorted out? If > >> > >> Yep, will look at this today. > > > > So I think we have a bigger problem than just copydir.c. It seems to > > me we should be fsyncing the table space data directories on every > > checkpoint. Otherwise any newly created relations or removed relations > > could disappear even though the data in them was fsynced. I'm thinking > > I should add an _mdfd_opentblspc(reln) call which returns a file > > descriptor for the tablespace and have mdsync() use that to sync the > > directory whenever it fsyncs a relation. It would be nice to remember > > which tablespaces have been fsynced and only fsync them once though, > > that would need another hash table just for tablespaces. > > > > We probably also need to fsync the pg_xlog directory every time we > > create or rename an xlog segment. > > > > Are there any other places we do directory operations which we need to > > be permanent? > > I agree with Tom that we need to see some actual reproducible test > cases where this is an issue before we go too crazy with it. In > theory what you're talking about could also happen when extending a > relation, if we extend into a new file; but I think we need to > convince ourselves that it really happens before we make any more > changes. Ok, will try to reproduce.
> On a pragmatic note, if this does turn out to be a problem, it's a > bug: and we can and do fix bugs whenever we discover them. But the > other part of this patch - to speed up createdb - is a feature - and > we are very rapidly running out of time for 9.0 features. So I'd like > to vote for getting the feature part of this committed (assuming it's > in good shape, of course) and we can continue to investigate the other > issues but without quite as much urgency. Sound sensible. Andres -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers