On Thu, Jun 27, 2019 at 1:52 AM Rui Wang <ruw...@google.com> wrote: >> >> >> AFAIK all streaming runners today practically do provide these panes in >> order; > > Does it refer to "the stage immediately after GBK itself processes fired > panes in order" in streaming runners? Could you share more information? > > >> >> this means that likely many users implicitly rely on this "non guarantee," >> probably without even knowing they are relying on it. > > If streaming runners have already provided or processed panes in order, and > likely many users rely on it already, why not make order of panes a part of > model explicitly?
Most runners produce panes in order, but they don't necessarily preserve the order downstream (at least beyond what's fused into the same stage, which is where it gets difficult).
