Guozhang, Both of Kafka's implementations of "StatusBackingStore" immediately delete the task from the backign store when you try to set it to DESTROYED, so we'd actually expect it to always be zero. A nonzero number of destroyed tasks would either indicate a new implementation of StatusBackingStore, or a malfunctioning StatusBackingStore (e.g. caches out of sync with compacted topic). This metric will usually be uninteresting, and was only included for completeness. It could possibly catch a bug.
Gwen, I had not considered this option. I agree there is an advantage to having more granular data about both connector and worker. The main disadvantage would be that it increases the number of metrics by a factor of num_workers, but I'd say this is an acceptable tradeoff. Another advantage of your suggestion is that the public interfaces for WorkerConnector would be unchanged, and the new metrics can be added within the Worker class. I've also updated the KIP to clarify that every task must have exactly one non-null task at all times. On Mon, Jun 17, 2019 at 1:41 PM Guozhang Wang <wangg...@gmail.com> wrote: > Hello Cyrus, > > Thanks for the KIP. I just have one nit question about Connect destroyed > tasks: is it an ever-increasing number? If yes, the corresponding metric > value would be increasing indefinitely as well. Is that intentional? > > Otherwise, lgtm. > > > Guozhang > > On Mon, Jun 17, 2019 at 1:14 PM Gwen Shapira <g...@confluent.io> wrote: > > > Sorry to join so late, but did we consider a single set of task-count > > metrics and using tags to scope each data point to a specific > > connector and worker (and in the future perhaps also user)? > > > > It will make analysis of the data easier - someone may want to > > breakdown tasks by both worker and connector to detect imbalanced > > assignments. > > > > Are there downsides to this approach? > > > > And a small nit: it will be good to capture in the KIP what are the > > expectations regarding overlap and disjointness of the proposed > > metrics. For example, is running+paused+failed = total? Can a task be > > failed and destroyed and therefore count in 2 of those metrics? > > > > On Thu, Jun 6, 2019 at 12:29 PM Cyrus Vafadari <cy...@confluent.io> > wrote: > > > > > > Konstantine, > > > > > > This is a good suggestion. Since the suggestion to add 2 additional > > > statuses analogous to the 3 proposed, it is a very minor change of no > > > structural consequence to the KIP. > > > > > > I've updated the KIP to incorporate your suggestion, and any voters who > > > disagree should definitely respond in the thread. > > > > > > Cyrus > > > > > > On Thu, Jun 6, 2019 at 11:16 AM Konstantine Karantasis < > > > konstant...@confluent.io> wrote: > > > > > > > Thanks Cyrus, > > > > > > > > this is a nice and straightforward addition. > > > > > > > > I'm +1 too, but I'd like to return with a question here as well > > regarding > > > > whether the unassigned tasks will be taken into account. > > > > Especially after KIP-415 we might start seeing this status for > specific > > > > periods of time. Therefore, I think it's a meaningful addition. > > > > Then there's the `destroyed` status which might be a lot more > > transient but > > > > we could also include for the sake of completion. > > > > Check org.apache.kafka.connect.runtime.AbstractStatus for the list of > > all > > > > possible statuses. > > > > > > > > Konstantine > > > > > > > > On Wed, Jun 5, 2019 at 4:32 PM Randall Hauch <rha...@gmail.com> > wrote: > > > > > > > > > Thanks, Cyrus. > > > > > > > > > > +1 (binding) > > > > > > > > > > Randall Hauch > > > > > > > > > > On Wed, Jun 5, 2019 at 10:36 AM Andrew Schofield < > > > > > andrew_schofi...@live.com> > > > > > wrote: > > > > > > > > > > > +1 (non-binding) > > > > > > > > > > > > Andrew Schofield > > > > > > > > > > > > On 05/06/2019, 14:04, "Ryanne Dolan" <ryannedo...@gmail.com> > > wrote: > > > > > > > > > > > > +1 (non-binding) > > > > > > > > > > > > Thanks > > > > > > Ryanne > > > > > > > > > > > > On Tue, Jun 4, 2019, 11:29 PM Cyrus Vafadari < > > cy...@confluent.io> > > > > > > wrote: > > > > > > > > > > > > > Hi all, > > > > > > > > > > > > > > Like like to start voting in the following KIP: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://nam01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcwiki.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-475%253A%2BNew%2BMetric%2Bto%2BMeasure%2BNumber%2Bof%2BTasks%2Bon%2Ba%2BConnector&data=02%7C01%7C%7C95f8a8ebb4a44882773808d6e9b65983%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636953366722392496&sdata=vbE%2BjrAapcQ68Vnwh5OkY1FFoOzFHs9rZRaPHlwqxSU%3D&reserved=0 > > > > > > > > > > > > > > Discussion thread: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://nam01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.apache.org%2Fthread.html%2Fbf7c92224aa798336c14d7e96ec8f2e3406c61879ec381a50652acfe%40%253Cdev.kafka.apache.org%253E&data=02%7C01%7C%7C95f8a8ebb4a44882773808d6e9b65983%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636953366722402501&sdata=0JpQuCpTKwJyOjWH8cM%2B6eU%2FjNT28eE7xvMOBQgghjA%3D&reserved=0 > > > > > > > > > > > > > > Thanks! > > > > > > > > > > > > > > Cyrus > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > Gwen Shapira > > Product Manager | Confluent > > 650.450.2760 | @gwenshap > > Follow us: Twitter | blog > > > > > -- > -- Guozhang >
