On Mon, Feb 6, 2017 at 1:42 AM, Kouhei Kaigai <kai...@ak.jp.nec.com> wrote: > I also had thought an idea to have extra space to Instrumentation structure, > however, it needs to make Instrumentation flexible-length structure according > to the custom format by CSP/FDW. Likely, it is not a good design. > As long as extension can retrieve its custom statistics on DSM area required > by ExecParallelEstimate(), I have no preference on the hook location.
That's what I had in mind: the hook happens there, but the extension retrieves the information from some extension-specific DSM area, just as it would on the ParallelFinish hook. > One thing we may pay attention is, some extension (not mine) may want to > collect worker's statistics regardless of Instrumentation (in other words, > even if plan is not under EXPLAIN ANALYZE). > It is the reason why I didn't put a hook under the > ExecParallelRetrieveInstrumentation(). I don't think you should worry about that as long as it's a hypothetical case. If/when some extension actually needs to do that, the design can be discussed with a real use case at hand, and not a hypothetical one. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
