Matthew Wakeling <matthew@xxxxxxxxxxx> writes: > Hmm. That problem is what WAL full-page-writes is meant to handle, isn't > it? So basically, if you're telling people that WAL full-page-writes is > safer than partial WAL, because it avoids updating pages in-place, then > you shouldn't be updating pages in-place for the hint bits either. You > can't win! This argument ignores the nature of the data change. With a hint-bit update, no data is being shuffled around, so there is no danger from a partial page write. A disk that leaves an individual sector corrupt would be a problem, but I don't think that's a huge risk. Keep in mind that disks aren't designed to just stop dead when power dies --- they are made to be able to park their heads before the juice is entirely gone. I think it's reasonable to assume they'll finish writing the sector in progress before they start parking. regards, tom lane
