On Fri, Dec 23, 2016 at 6:33 AM, Jim Nasby <jim.na...@bluetreble.com> wrote: > On 12/22/16 12:02 PM, Andres Freund wrote: >> >> >> On December 22, 2016 6:44:22 PM GMT+01:00, Robert Haas >> <robertmh...@gmail.com> wrote: >>> >>> On Thu, Dec 22, 2016 at 12:39 PM, Andres Freund <and...@anarazel.de> >>> wrote: >>>> >>>> It makes more sense of you mentally separate between filename(s) and >>> >>> file contents. Having to do filesystem metatata transactions for an >>> fsync intended to sync contents would be annoying... >>> >>> I thought that's why there's fdatasync. >> >> Not quite IIRC: that doesn't deal with file size increase. All this would >> be easier if hardlinks wouldn't exist IIUC. It's basically a question >> whether dentry, inode or contents need to be synced. Yes, it sucks. > > > IIRC this isn't the first time we've run into this problem... should > pg_fsync() automatically fsync the directory as well? I guess we'd need a > flag to disable that for performance critical areas where we know we don't > need it (presumably just certain WAL fsyncs).
I am not sure if that would be performance-wise. The case of the 2PC files is quite special anyway as just doing the sync at checkpoint phase for everything would be enough. -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
