Too frequent read protection is already handled in the patch but these comments might lead it into new directions. Current implementation had this same limit that file was written no more than once per 500 ms.
> Some sort of "if stats were requested in the last 500 ms, just tell the > requester to read the existing file".
> Things that come to mind:
> - autovacuum could use a more frequent stats update in certain cases
BTW, we could implement that by, instead of having a global tunable, including a field in the request message saying how stale an existing file is acceptable for this requestor. 500ms might be the standard value but autovac could use a smaller number.
