On Thu, Sep 5, 2013 at 1:55 AM, Andres Freund <and...@2ndquadrant.com> wrote: > On 2013-09-04 09:23:20 -0700, Jeff Davis wrote: >> On Wed, 2013-09-04 at 11:32 -0400, Tom Lane wrote: >> > Jeff Davis <pg...@j-davis.com> writes: >> > > 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. >> > >> > Isn't this whole discussion academic in view of Andres' point? >> >> Maybe "complex code" was an overstatement. We'd be able to eliminate the >> XLOG_FPW_CHANGE, UpdateFullPageWrites(), and one of the members of >> XLogCtlInsert; and make xlog.c slightly shorter in the process. > > That path is also executed during a normal restart and during > promotion. Check the invocation of UpdateFullPageWrites() in > StartupXLOG(). Note that a standby needs to be able to follow a > primaries full_page_writes setting during a promotion.
Yes, this is required for the backup from the standby. If we make the GUC contect to PGC_POSTMASTER, I think that we can remove XLOG_FPW_CHANGE and treat full_page_writes the same way as wal_level, max_connections, i.e., the parameter which CheckRequiredParameterValues() handles. Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
