On 5/9/25 18:09, Peter Geoghegan wrote: > On Fri, May 9, 2025 at 11:55 AM Peter Geoghegan <p...@bowt.ie> wrote: >> Note that "sizeof(FmgrInfo)" is 48 bytes. Prior to skip scan, >> RelationData.rd_supportinfo would have required 48*5=240 bytes. After >> skip scan, it would have required 48*6=288 bytes. Maybe 256 bytes is >> some kind of critical threshold, someplace? > > Can you try it with the attached patch? > > The patch disables skip support entirely, in a way that should > eliminate whatever the inherent overhead of adding a sixth support > routine to nbtree was. It does not remove skip scan itself (that > should still work with queries that are actually eligible to use skip > scan, albeit slightly less efficiently with some opclasses). >
Tried, doesn't seem to affect the results at all. -- Tomas Vondra
