Hi Dong! Let me try to answer the questions :)
1 : busyTimeMsPerSecond is not specific for CPU, it measures the time spent in the main record processing loop for an operator if I understand correctly. This includes IO operations too. 2: We should add this to the FLIP I agree. It would be a Duration config with the expected catch up time after rescaling (let's say 5 minutes). It could be computed based on the current data rate and the calculated max processing rate after the rescale. 3: In the current proposal we don't have per operator configs. Target utilization would apply to all operators uniformly. 4: It should be configurable, yes. 5,6: The names haven't been finalized but I think these are minor details. We could add concrete names to the FLIP :) Cheers, Gyula On Sun, Nov 6, 2022 at 5:19 PM Dong Lin <lindon...@gmail.com> wrote: > Hi Max, > > Thank you for the proposal. The proposal tackles a very important issue > for Flink users and the design looks promising overall! > > I have some questions to better understand the proposed public interfaces > and the algorithm. > > 1) The proposal seems to assume that the operator's busyTimeMsPerSecond > could reach 1 sec. I believe this is mostly true for cpu-bound operators. > Could you confirm that this can also be true for io-bound operators such as > sinks? For example, suppose a Kafka Sink subtask has reached I/O bottleneck > when flushing data out to the Kafka clusters, will busyTimeMsPerSecond > reach 1 sec? > > 2) It is said that "users can configure a maximum time to fully process > the backlog". The configuration section does not seem to provide this > config. Could you specify this? And any chance this proposal can provide > the formula for calculating the new processing rate? > > 3) How are users expected to specify the per-operator configs (e.g. target > utilization)? For example, should users specify it programmatically in a > DataStream/Table/SQL API? > > 4) How often will the Flink Kubernetes operator query metrics from > JobManager? Is this configurable? > > 5) Could you specify the config name and default value for the proposed > configs? > > 6) Could you add the name/mbean/type for the proposed metrics? > > > Cheers, > Dong > > >