On 7/10/15 4:46 AM, Simon Riggs wrote:
On 10 July 2015 at 09:49, Sawada Masahiko <sawada.m...@gmail.com <mailto:sawada.m...@gmail.com>> wrote:> It is a minor thing, but if there is no other use for this fourth > "bit-space", it seems a shame to waste it when there is some use for it. I > haven't looked at the code around this area to know how hard it would be to > implement the setting and clearing of the bit. I think so too, we would be able to use unused fourth status of bits efficiently. Should I include these improvement into this patch? This topic should be discussed on another thread after this feature is committed, I think. The impossible state acts as a diagnostic check for us to ensure the bitmap is not itself corrupt. -1 for using it for another purpose.
AFAICS empty page is only interesting for vacuum truncate, which is a very short-term thing. It would be better to find a way to handle that differently.
In any case, that should definitely be a separate discussion from this patch.
-- Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX Data in Trouble? Get it in Treble! http://BlueTreble.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
