Gregory Stark wrote: > Alvaro Herrera <[EMAIL PROTECTED]> writes: > > > Alvaro Herrera wrote: > > > >> The "other hint bits" are: > >> > >> - LP_DEAD as used by the various callers of ItemIdMarkDead. > >> - PD_PAGE_FULL > >> - BTPageOpaque->btpo_flags and btpo_cycleid > >> > >> All of them are changed with only SetBufferCommitInfoNeedsSave being > >> called afterwards. > > > > I think we could get away with WAL-logging LP_DEAD via ItemIdMarkDead > > similar to what is done to SetHintBits in the posted patch, and cope > > with the rest by marking the page with the invalid checksum; they are > > not so frequent anyway so the reliability loss is low. > > If PD_PAGE_FULL is set and that causes the crc to be set to the invalid sum > will we ever get another chance to set it?
I should have qualified that a bit more. It's not setting PD_FULL that's not logged, but clearing it (heap_prune_page, line 282). It's set in heap_update. Hmm, oh I see another problem here -- the bit is not restored when replayed heap_update's WAL record. I'm now wondering what other bits are set without much care about correctly restoring them during replay. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
