Hi, On 2023-10-11 16:09:21 +0200, Matthias van de Meent wrote: > On Wed, 11 Oct 2023 at 01:29, Andres Freund <and...@anarazel.de> wrote: > > > After that we'll only have the system ID left from the extended > > > header, which we could store across 2 pages in the (current) alignment > > > losses of xlp_rem_len - even pages the upper half, uneven pages the > > > lower half of the ID. This should allow for enough integrity checks > > > without further increasing the size of XLogPageHeader in most > > > installations. > > > > I doubt that that's a good idea - what if there's just a single page in a > > segment? And there aren't earlier segments? That's not a rare case, IME. > > Then we'd still have 50% of a system ID which we can check against for > any corruption. I agree that it increases the chance of conflics, but > it's still strictly better than nothing at all.
A fair point - I somehow disregarded that all bits in the system id are equally meaningful. Greetings, Andres Freund
