> Reduction of contention for pg_clog access, for one thing. If you read
> the archives, you'll find that pg_clog access contention has been shown
> to be one cause of "context swap storms". Having to go to clog for
> every single tuple access would make that orders of magnitude worse.
Ok; is it the
"Wierd context-switching issue on Xeon"
thread? Or that has nothing to do with it? I tried "context swap storms
pg_clog" but I didn't get anything...
> More generally, we're not going to give up hint bits even if there are
> identifiable workloads where they don't buy much --- because there are
> many others where they do.
Sure: I wasn't suggesting to give up them, just to make their usage
"user selectable" (and "on" by default)