Melanie Plageman <melanieplage...@gmail.com> writes: > On Wed, Jul 20, 2022 at 11:35 AM Greg Stark <st...@mit.edu> wrote: >> It seems like if we really think the total number of database objects >> is reasonably limited to scales that fit in RAM there would be a much >> simpler database design that would just store the catalog tables in >> simple in-memory data structures and map them all on startup without >> doing all the work Postgres does to make relational storage scale.
> I think efforts to do such a thing have gotten caught up in solving > issues around visibility and managing the relationship between local and > global caches [1]. It doesn't seem like the primary technical concern > was memory usage. AFAIR, the previous stats collector implementation had no such provision either: it'd just keep adding hashtable entries as it received info about new objects. The only thing that's changed is that now those entries are in shared memory instead of process-local memory. We'd be well advised to be sure that memory can be swapped out under pressure, but otherwise I'm not seeing that things have gotten worse. regards, tom lane