On Monday, June 18, 2012 11:51:27 PM Daniel Farina wrote: > On Mon, Jun 18, 2012 at 8:50 AM, Andres Freund <and...@2ndquadrant.com> wrote: > >> * Size of field. 16 bits is enough for 32,000 master nodes, which is > >> quite a lot. Do we need that many? I think we may have need for a few > >> flag bits, so I'd like to reserve at least 4 bits for flag bits, maybe > >> 8 bits. Even if we don't need them in this release, I'd like to have > >> them. If they remain unused after a few releases, we may choose to > >> redeploy some of them as additional nodeids in future. I don't foresee > >> complaints that 256 master nodes is too few anytime soon, so we can > >> defer that decision. > > > > I wished we had some flag bits available before as well. I find 256 nodes > > a pretty low value to start with though, 4096 sounds better though, so I > > would be happy with 4 flag bits. I think for cascading setups and such > > you want to add node ids for every node, not only masters... > > > > Any opinions from others on this? > > What's the cost of going a lot higher? Because if one makes enough > numerical space available, one can assign node identities without a > coordinator, a massive decrease in complexity. It would increase the size of every wal record. We just have 16bit left there by chance...
Andres -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
