On Tue, Jan 30, 2018 at 10:10 PM, Amit Kapila <amit.kapil...@gmail.com> wrote: >> known_started_workers looks a lot like any_message_received. Perhaps >> any_message_received should be renamed to known_started_workers and >> reused here. > > Sure, that sounds good to me. Do you prefer a separate patch for > renaming any_message_received to known_started_workers or is it okay > to have it along with the main patch?
A single patch sounds OK. >> After all, if we know that a worker was started, there's >> no need for WaitForParallelWorkersToFinish to again call >> GetBackgroundWorkerPid() for it. > > I think in above sentence you wanted to say > WaitForParallelWorkersToAttach, not WaitForParallelWorkersToFinish. > Am I right? Yes. >> I think that you shouldn't need the 10ms delay loop; waiting forever >> should work. If a work fails to start, the postmaster should send >> SIGUSR1 which should set our latch. >> > I am not getting what exactly you are suggesting here. The wait loop > is intended for the case when some workers are not started. We want > to wait for sometime before checking again whether workers are > started. I wanted to avoid busy looping waiting for some worker to > start. I think in most cases we don't need to wait, but for some > corner cases where postmaster didn't get chance to start a worker, we > should avoid busy looping waiting for a worker to start. I agree we need to avoid busy-looping. What I'm saying is that we don't need a timeout. Why do you think we need a timeout? We have bgw_notify_pid so that we will get a signal instead of having to poll. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
