On Tue, 2013-09-03 at 15:42 -0400, Robert Haas wrote: > Although this is true, the administrator's estimate of whether that > guarantee is or is not provided might not be as consistent as the > hardware behavior itself. I am generally of the feeling that having > to restart the server to change setting sucks, and while it surely > sucks less for this setting than some, mostly because few people > change this setting in the first place, I'm still not convinced that > this is moving in the right direction.
I think code complexity matters quite a lot. If we can eliminate some complex code in a complex area, and all we give up is a feature with essentially no use case, that sounds like we're moving in the right direction to me. I suppose some might be using it as a hack when they really just want to temporarily disable WAL during a load or something. Seems like a blunt tool though, and I haven't heard of anyone doing that or suggesting it. And it doesn't store the page hole anyway, so the FPI during a load is ordinarily quite small. > > Then, I intend to write another patch to make the full-page writes for > > checksums honor the full_page_writes setting. That will be easier to > > write once it's a PGC_POSTMASTER. > > I don't think I know exactly what this means. XLogSaveBufferForHint() calls XLogCheckBuffer() but doesn't also look at the full page writes setting (like in XLogInsert()). That means, if checksums are enabled and full_page_writes is off, we'll still write some full page images for checksums. I'd like to remedy that. Regards, Jeff Davis -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers