On 3/4/21 4:16 PM, Tom Lane wrote: > Tomas Vondra <tomas.von...@enterprisedb.com> writes: >> IMO just bumping up the constants from ~65k to 1M is a net loss, for >> most users. We add this to bitmapsets, which means we're using ~8kB with >> the current values, but this jumps to 128kB with this higher value. This >> also means bms_next_member etc. have to walk much more memory, which is >> bound to have some performance impact for everyone. > > Hmm, do we really have any places that include OUTER_VAR etc in > bitmapsets? They shouldn't appear in relid sets, for sure. > I agree though that if they did, this would have bad performance > consequences. >
Hmmm, I don't know. I mostly assumed that if I do pull_varnos() it would include those values. But maybe that's not supposed to happen. > I still think the negative-special-values approach is better. > If there are any places that that would break, we'd find out about > it in short order, rather than having a silent performance lossage. > OK regards -- Tomas Vondra EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
