Hi Thomas, Thanks for the explanation. Does it mean I cannot reproduce the real-time behavior of the replayed trace? Say the watermarks are perfect and FixedWindows groups elements into 1-minute windows, will the watermarks trigger the FixedWindows to fire roughly every minute?
I am a little confused about the "when available" behavior of the runner. Since the watermarks emitted by the BoundedSource will always be BoundedWindow.TIMESTAMP_MIN_VALUE except for the last watermark, how could the runner know when to trigger the computation on a window? Thanks, Shen On Fri, Apr 28, 2017 at 1:13 PM, Thomas Groh <[email protected]> wrote: > You can't directly control the watermark that a BoundedSource emits. > Windowing into FixedWindows will still work as you expect, however: your > elements will be assigned to their windows based on the time the event > occurred. Depending on the runner, triggers may be run either "when > available" or after all the work is completed, but your output data will be > as if you had a perfect watermark. > > On Fri, Apr 28, 2017 at 10:09 AM, Shen Li <[email protected]> wrote: > > > Hi, > > > > Say I want to replay a data trace of last week using fixed windows. The > > data trace is read from a file using TextIO. In order to trigger windows > at > > right times, how can I control the watermark emitted by the > BoundedSource? > > > > Thanks, > > > > Shen > > >
