Re: Is full_page_writes=off safe in conjunction with PITR?

Bruce Momjian <pgman@candle.pha.pa.us> writes:
> I am thinking we should throw an error on pg_start_backup() and
> pg_stop_backup if full_page_writes is off.

No, we'll just change the test in xlog.c so that fullPageWrites is
ignored if XLogArchivingActive.

> Seems archive_command and
> full_page_writes can still be used if we are not in the process of doing
> a file system backup.

Think harder: we are only safe if the first write to a given page after
it's mis-copied by the archiver is a full page write.  The requirement
therefore continues after pg_stop_backup.  Unless you want to add
infrastructure to keep track for *every page* in the DB of whether it's
been fully written since the last backup?
        regards, tom lane