Sorry, forgot the link for reference [1], which is https://ci.apache.org/projects/flink/flink-docs-release-1.6/dev/datastream_api.html#controlling-latency
> Am 20.09.2018 um 16:36 schrieb Stefan Richter <s.rich...@data-artisans.com>: > > Hi, > > you provide not very much information for this question, e.g. what and how > exactly your measure, if this is a local or distributed setting etc. I assume > that it is distributed and that the cause for your observation is the buffer > timeout, i.e. the maximum time that Flink waits until sending a buffer with > just one element, which happens to be 100ms by default. You can decrease this > value to some extend, at to cost of potential loss in throughput, but I think > even values around 5-10ms are ok-ish. See [1] for more details. If you want > to reduce latency between chained operators, you can also try to disable > object-reuse: > > StreamExecutionEnvironment env = > StreamExecutionEnvironment.getExecutionEnvironment(); > env.getConfig().enableObjectReuse(); > > Best, > Stefan > >> Am 20.09.2018 um 16:03 schrieb James Yu <cyu...@gmail.com >> <mailto:cyu...@gmail.com>>: >> >> The previous email seems unable to display embedded images, let me put on >> the links. >> Hi, >> >> My team and I try to measure total time spent on our flink job and found out >> that Flink takes 40ms ~ 100ms to proceed from one operator to another. I >> wonder how can we reduce this transition time. >> >> Following DAG represents our job: >> https://drive.google.com/open?id=1wNR8po-SooAfYtCxU3qUDm4-hm16tclV >> <https://drive.google.com/open?id=1wNR8po-SooAfYtCxU3qUDm4-hm16tclV> >> >> >> and here is the screenshot of our log: >> https://drive.google.com/open?id=14PTViZMkhagxeNjOb4R8u3BEr7Ym1xBi >> <https://drive.google.com/open?id=14PTViZMkhagxeNjOb4R8u3BEr7Ym1xBi> >> >> at 19:37:04.564, the job is leaving "Source: Custom Source -> Flat Map" >> at 19:37:04.605, the job is entering "Co-Flat Map" >> at 19:37:04.605, the job is leaving "Co-Flat Map" >> at 19:37:04.705, the job is entering "Co-Flat Map -> ...." >> at 19:37:04.708, the job is leaving "Co-Flat Map -> ..." >> >> both "Co-Flat Map" finishes merely instantly, while most of the execution >> time is spent on the transition. Any idea? >> >> >> This is a UTF-8 formatted mail >> ----------------------------------------------- >> James C.-C.Yu >> +886988713275 >> +8615618429976 >> >
