Hi Chesnay,
IIUC, our only disagreement is whether to support task info in
the metric format. But we all agree with the default metric
format
"metrics.scope.jm-operator=<host>.jobmanager.<job_name>.<operator_name>"
which doesn't include task info, right?
Regarding "coordinator metrics don't *belong to* any
tasks/vertexes", I mean the coordinator doesn't run on specific
tasks, so it doesn't have runtime information of tasks. My
concern about adding task info to the coordinator metric is that
1) if we register coordinator metrics for every subtask, the
number of coordinator metrics will be exploded when task
parallelism is large. This is an overhead to JM & metric systems,
and the duplicated metrics are useless for users.
2) Correct me if I'm wrong, MetricGroup#counter only supports
registering one metric. It seems it can't register a metric
reporting for multiple metric names (e.g. multiple subtasks).
Best,
Jark
On Mon, 30 Jan 2023 at 16:11, Chesnay Schepler
<ches...@apache.org> wrote:
I hadn't looked in detail in to how the task info can be
introduced, but
given that the coordinates are created by the execution
graph, where we
only work on tasks, it should be possible and rather simple.
The OperatorCoordinatorHolder gets access to the
ExecutionJobVertex from
which it can extract everything and create the task/operator
groups.
Exposure to the coordinator could happen via the coordinator
context as
originally planned.
> As we know, coordinator metrics are just like
JMJobMetricGroup, which
don't belong to any tasks/vertexes.
I don't think this is true, every coordinator is scoped to a
specific
operator, and every operator is associated with a particular
vertex.
From the javadocs:
" A coordinator for runtime operators. The
OperatorCoordinator runs on
the master, associated with
the job vertex of the operator. It communicates with
operators via
sending operator events."
On 28/01/2023 09:15, Jark Wu wrote:
> Hi all,
>
> IIUC, Chesnay means we should have a more general metric
group for
> **operator**
> not for **coordinator** in JM, this would be useful to extend
> other operator-specific
> metrics in the future. That means the new scope format
should be designed
> for
> the operator,
> e.g.,
metrics.scope.jm-operator=<host>.jobmanager.<job_name>.<operator_name>
> The coordinator metric is a subgroup (a constant
"coordinator" suffix) of
> the JMOperatorMG.
>
> I think this is a nice design. However, I have a question
about adding task
> id/name to this list.
> How to get the task id/name when reporting a coordinator
metric? As we
> know, coordinator metrics
> are just like JMJobMetricGroup, which don't belong to any
tasks/vertexes.
> Do you mean reporting
> coordinator metrics for every task id under the operator?
>
> Best,
> Jark
>
>
> On Thu, 19 Jan 2023 at 17:33, Chesnay Schepler
<ches...@apache.org> wrote:
>
>> > First, I do not understand why users have to configure
the new scope
>> format, which has a default value.
>>
>> If you don't use scope formats, sure. If you do use scope
formats, e.g.
>> to add a common prefix (which is the case for datadog
users for
>> example), then the current default in the FLIP is
insufficient and
>> requires the user to update the configuration.
>>
>> > I usually do not need to change these configuration of
scope formats
>> when submitting the flink job.
>>
>> Scope formats as a whole are quite a power-user feature,
but that
>> doesn't mean we should ignore it.
>>
>> > I try to let it extend the ComponentMetricGroup
>>
>> This isn't inherently required just because it is a
"component".
>> Component metric groups should _only_ be used for cases
where such a
>> component provides several bits of metadata.
>> For example, tasks provide vertex ids, task names,
attempted IDs etc.,
>> and we'd like users to have the option on how this
metadata ends up
>> being used (via scope formats). This currently can't be
built with the
>> addGroup() methods, hence why the component groups exist.
>> However, the operator coordinator _itself_does not provide
several bits
>> of metadata. Logically, the _operator_ does, not the
coordinator.
>>
>> > This make me decide to add a new scope format.
>>
>> And this is fine; just don't add a new scope format for
the coordinator
>> but logically for operators on the JM side, such that we
can extend the
>> set of operator-specific metrics in the future without
having to add yet
>> another scope format.
>>
>> > The relationship between the Operator and
OperatorCoordinator is
>> maintained in the OperatorCoordinatorHolder. In the POC,
the operator
>> name/id could be found and the
OperatorCoordinatorMetricGroup will be
>> created here.
>>
>> That's all irrelevant.
>>
>> > The registered metrics of OperatorCoordinator always
are those which
>> can not be aggregated from the tasks, like the number of
unassigned
>> splits in the SourceCoordinator. Actually we have not
encountered the
>> scenario you mentioned. I think the
OperatorCoordinatorMetricGroup
>> should only contain the metrics for itself instead of its
subtasks.
>>
>> You are misunderstanding the problem.
>>
>> This isn't about aggregating metrics on our side or
exposing metrics
>> from TMs on the JM side or anything like that.
>>
>> It's purely about the available metadata for operator
metrics on the JM
>> side. Currently you suggest operator name / id; what I'm
proposing is to
>> add task(==vertex!) id / name to this list.
>>
>> The benefit here is simple. I can look up all metrics
where task_id==XXX
>> and get _everything_ related to that vertex, including all
metrics
>> associated with operators that are part of that vertex,
including the
>> coordinator.
>>
>> > Using metrics.scope.jm.job is not enough to
distinguish the different
>> coordinators.
>>
>> I did not suggest just using metrics.scope.jm.job. I
suggested that as
>> the default for the jm operator scope format, that is used
for the
>> proposed JobManagerOperatorMetricGroup, which will have
some plain
>> metric groups as children for coordinators.
>> Aka, you have the JMOperatorMG, then you call
addGroup("coordinators")
>> and then addGroup(coordinator_name) for each coordinator.
>>
>> > So there are two choice for the
>> InternalOperatorCoordinatorMetricGroup: 1. add and improve
the new scope
>> format; 2. use the metrics.scope.jm.job and
ProxyMetricGroup. Which one
>> is better?
>>
>> There are more options than that.
>> I feel like there are a lot of misunderstandings in this
discussion.
>> Please let me know if I could clear things up. If not I
can also provide
>> a PoC based on your PoC if that can speed things up. It's
not that
>> different anyway.
>>
>> On 19/01/2023 07:39, Hang Ruan wrote:
>>> Hi, chesnay,
>>>
>>> Thanks for your reply. I still have some doubts about the
questions
>>> you raised.
>>>
>>> > Extending the set of ScopeFormats is problematic
because it in
>>> practice
>>> it breaks the config if users actively rely on it,
since there's now
>>> another key that they _must_ set for it to be
>>> consistent/compatible with
>>> their existing setup.
>>> Unfortunately due to how powerful scope formats are
we can't derive a
>>> default value that matches their existing setup.
>>> Hence we should try to do this as rarely as possible.
>>>
>>>
>>> > This FLIP does not adhere to that since it
proposes a dedicated
>>> format
>>> for coordinators; next time we want to expose
operator-specific
>>> metrics
>>> (e.g., in the scheduler) we'd have to add another
one to support it.
>>>
>>>
>>> First, I do not understand why users have to configure
the new scope
>>> format, which has a default value. I usually do not need
to change
>>> these configuration of scope formats when submitting the
flink job.
>>> IMO, the OperatorCoordinator is a component running at
the JobMaster.
>>> I try to let it extend the ComponentMetricGroup, but I
cannot find
>>> a suitable scope. This make me decide to add a new scope
format.
>>>
>>> > Additionally, the configurable variables (operator
name/id) are
>>> logically not attached to the coordinator, but
operators, so to me it
>>> just doesn't make sense to structure it like this.
>>>
>>>
>>> The relationship between the Operator and
OperatorCoordinator is
>>> maintained in the OperatorCoordinatorHolder. In the POC,
the operator
>>> name/id could be found and the
OperatorCoordinatorMetricGroup will be
>>> created here.
>>>
>>> > Another thing I'm concerned about is that, because
we don't include
>>> tasks in the hierarchy, users wishing to collect all
metrics for a
>>> particular task (in this case ==vertex) now have to go
>>> significantly out
>>> of their way to get them, since they can no longer
just filter by the
>>> task ID but have to be filter for _all_ operators
that are part of
>>> the task.
>>>
>>>
>>> The registered metrics of OperatorCoordinator always are
those which
>>> can not be aggregated from the tasks, like the number of
unassigned
>>> splits in the SourceCoordinator. Actually we have not
encountered the
>>> scenario you mentioned. I think the
OperatorCoordinatorMetricGroup
>>> should only contain the metrics for itself instead of its
subtasks.
>>>
>>> Using metrics.scope.jm.job is not enough to distinguish
the different
>>> coordinators. The operator id/name is necessary. Then
>>> the implementation should be like this. But users can not
change the
>>> scope in this way. This is also acceptable.
>>> @Internal public class InternalOperatorCoordinatorMetricGroup
>>> extends ProxyMetricGroup<MetricGroup>
>>> implements OperatorCoordinatorMetricGroup {
>>> public InternalOperatorCoordinatorMetricGroup(
>>> JobManagerJobMetricGroup parent, OperatorID
operatorID,
>> String operatorName) {
>>> super(parent.addGroup(operatorID +
>> operatorName).addGroup("coordinator")); }
>>> }
>>> So there are two choice for the
>>> InternalOperatorCoordinatorMetricGroup: 1. add and
improve the new
>>> scope format; 2. use the metrics.scope.jm.job and
ProxyMetricGroup.
>>> Which one is better?
>>>
>>> Best,
>>> Hang
>>>
>>>
>>> Chesnay Schepler <ches...@apache.org> 于2023年1月18日周三
17:03写道：
>>>
>>> You're misunderstanding the problem.
>>>
>>> Metric groups form a tree with each group providing
certain metadata.
>>>
>>> E.g., on the taskmanager we have a TM metric group
that provides info
>>> about the TM, that has child task metric groups,
that have child
>>> operator metric groups etc. The operator metric
group again has
>>> children, where we are now mostly in the
user/connector land, like a
>>> kafka metric group providing partition info or
something.
>>>
>>> What is being proposed is to create a coordinator
metric group on
>>> the JM
>>> side that provides operator metadata.
>>>
>>> A more appropriate structure is to create an
operator group on the JM
>>> side that provides this info, with the coordinator
metric group
>>> being a
>>> child.
>>>
>>> On 17/01/2023 19:56, Steven Wu wrote:
>>> >> Additionally, the configurable variables
(operator name/id) are
>>> > logically not attached to the coordinator, but
operators, so to
>>> me it
>>> > just doesn't make sense to structure it like this.
>>> >
>>> > Chesnay, maybe we should clarify the terminology.
To me,
>>> pperators (like
>>> > FLIP-27 source) can have two parts (coordinator and
>>> reader/subtask). I
>>> > think it is fine to include operator name/id for
coordinator
>>> metrics.
>>> >
>>> > On Mon, Jan 16, 2023 at 2:13 AM Chesnay Schepler
>>> <ches...@apache.org> wrote:
>>> >
>>> >> Slight correction: Using metrics.scope.jm.job as
the default
>>> should be
>>> >> safe.
>>> >>
>>> >> On 16/01/2023 10:18, Chesnay Schepler wrote:
>>> >>> The proposed ScopeFormat is still problematic
for a few reasons.
>>> >>>
>>> >>> Extending the set of ScopeFormats is problematic
because it in
>>> >>> practice it breaks the config if users actively
rely on it, since
>>> >>> there's now another key that they _must_ set for
it to be
>>> >>> consistent/compatible with their existing setup.
>>> >>> Unfortunately due to how powerful scope formats
are we can't
>>> derive a
>>> >>> default value that matches their existing setup.
>>> >>> Hence we should try to do this as rarely as
possible.
>>> >>>
>>> >>> This FLIP does not adhere to that since it
proposes a
>>> dedicated format
>>> >>> for coordinators; next time we want to expose
operator-specific
>>> >>> metrics (e.g., in the scheduler) we'd have to
add another one to
>>> >>> support it.
>>> >>>
>>> >>> Additionally, the configurable variables
(operator name/id) are
>>> >>> logically not attached to the coordinator, but
operators, so
>>> to me it
>>> >>> just doesn't make sense to structure it like this.
>>> >>>
>>> >>> Another thing I'm concerned about is that,
because we don't
>>> include
>>> >>> tasks in the hierarchy, users wishing to collect
all metrics for
>> a
>>> >>> particular task (in this case ==vertex) now have
to go
>>> significantly
>>> >>> out of their way to get them, since they can no
longer just
>>> filter by
>>> >>> the task ID but have to be filter for _all_
operators that are
>>> part of
>>> >>> the task.
>>> >>>
>>> >>> On 16/01/2023 03:09, Hang Ruan wrote:
>>> >>>> Hi, @ches...@apache.org <ches...@apache.org> ,
>>> >>>>
>>> >>>> Do you have time to help to review this FLIP
again after the
>>> >>>> modification?
>>> >>>> Looking forward to your reply.
>>> >>>> This FLIP will add a new configuration for the
>>> >>>> OperatorCoordinatorMetricGroup scope format. It
provides an
>>> internal
>>> >>>> implementation and is added as a component to the
>>> >>>> JobManagerJobMetricGroup.
>>> >>>> If something doesn't make sense, could you
provide some
>>> advice? It
>>> >>>> will be
>>> >>>> very helpful. Thanks a lot for your help.
>>> >>>>
>>> >>>> Best,
>>> >>>> Hang
>>> >>>>
>>> >>>> Martijn Visser <martijnvis...@apache.org>
于2023年1月11日周三
>>> 16:34写道：
>>> >>>>
>>> >>>>
>>> >>>>> Hi Hang,
>>> >>>>>
>>> >>>>> I'm a bit surprised that this has gone to a
vote, given that
>>> Chesnay
>>> >>>>> deliberately mentioned that he would vote
against it as-is.
>>> I would
>>> >>>>> expect
>>> >>>>> that before going to a vote, he has had the
opportunity to
>>> >>>>> participate in
>>> >>>>> this discussion.
>>> >>>>>
>>> >>>>> Best regards,
>>> >>>>>
>>> >>>>> Martijn
>>> >>>>>
>>> >>>>> On Tue, Jan 3, 2023 at 12:53 PM Jark Wu
<imj...@gmail.com>
>>> wrote:
>>> >>>>>
>>> >>>>>> Hi Dong,
>>> >>>>>>
>>> >>>>>> Regarding
“SplitEnumeratorContext#metricGroup”, my only
>>> concern is
>>> >>>>>> that
>>> >>>>>> this is a core interface for the FLIP. It’s
hard to tell how
>>> >>>>>> sources use
>>> >>>>>> metric group without mentioning this
interface. Even if
>>> this is an
>>> >>>>> existing
>>> >>>>>> API, I think it’s worth introducing the
interface again and
>>> declaring
>>> >>>>> that
>>> >>>>>> we will implement the interface instead of a
no-op method
>>> in this
>>> >>>>>> FLIP.
>>> >>>>>>
>>> >>>>>> Anyway, this is a minor problem and shouldn’t
block this
>>> FLIP. I’m
>>> >>>>>> +1 to
>>> >>>>>> start a vote.
>>> >>>>>>
>>> >>>>>> Best,
>>> >>>>>> Jark
>>> >>>>>>
>>> >>>>>>
>>> >>>>>>> 2023年1月3日 10:03，Hang Ruan
<ruanhang1...@gmail.com> 写道：
>>> >>>>>>>
>>> >>>>>>> Hi, Jark and Dong,
>>> >>>>>>>
>>> >>>>>>> Thanks for your comments. Sorry for my late
reply.
>>> >>>>>>>
>>> >>>>>>> For suggestion 1, I plan to implement the
>>> >>>>>>> SplitEnumeratorMetricGroup in
>>> >>>>>>> another issue, and it is not contained in
this FLIP. I
>>> will add some
>>> >>>>>>> description about this part.
>>> >>>>>>> For suggestion 2, changes about
>>> OperatorCoordinator#metricGroup has
>>> >>>>>> already
>>> >>>>>>> been documented in the proposed change section.
>>> >>>>>>>
>>> >>>>>>> Best,
>>> >>>>>>> Hang
>>> >>>>>>>
>>> >>>>>>> Dong Lin <lindon...@gmail.com>
于2023年1月1日周日 09:45写道：
>>> >>>>>>>
>>> >>>>>>>> Let me chime-in and add comments regarding
the public
>>> interface
>>> >>>>> section.
>>> >>>>>>>> Please see my comments inline.
>>> >>>>>>>>
>>> >>>>>>>> On Thu, Dec 29, 2022 at 6:08 PM Jark Wu
>>> <imj...@gmail.com> wrote:
>>> >>>>>>>>
>>> >>>>>>>>> Hi Hang,
>>> >>>>>>>>>
>>> >>>>>>>>> Thanks for driving this discussion. I
think this is a
>>> very useful
>>> >>>>>> feature
>>> >>>>>>>>> for connectors.
>>> >>>>>>>>>
>>> >>>>>>>>> The FLIP looks quite good to me, and I
just have two
>>> suggestions.
>>> >>>>>>>>>
>>> >>>>>>>>> 1. In the "Public Interface" section,
mention that the
>>> >>>>>>>>> implementation
>>> >>>>>>>>> behavior of
"SplitEnumeratorContext#metricGroup" is
>>> changed from
>>> >>>>>>>> returning
>>> >>>>>>>>> null to returning a concrete
SplitEnumeratorMetricGroup
>>> instance.
>>> >>>>> Even
>>> >>>>>>>>> though the API is already there, the
behavior change can
>>> also be
>>> >>>>>>>> considered
>>> >>>>>>>>> a public change.
>>> >>>>>>>>>
>>> >>>>>>>> SplitEnumeratorContext#metricGroup is an
interface and
>>> this FLIP
>>> >>>>>>>> does
>>> >>>>>> not
>>> >>>>>>>> seem to change its semantics/behavior. The
FLIP does
>>> change the
>>> >>>>>>>> implementation/behavior of
>>> SourceCoordinatorContext#metricGroup,
>>> >>>>>>>> which
>>> >>>>>> is
>>> >>>>>>>> marked @Internal.
>>> >>>>>>>>
>>> >>>>>>>> Thus it might seem a bit weird to add in
the public
>> interface
>>> >>>>>>>> section
>>> >>>>>>>> saying that we change the interface
>>> >>>>>>>> SplitEnumeratorContext#metricGroup
>>> >>>>>> from
>>> >>>>>>>> returning null to non-null object.
>>> >>>>>>>>
>>> >>>>>>>> 2. Mention the newly added interface of
>>> >>>>>> "OperatorCoordinator#metricGroup"
>>> >>>>>>>>> in the "Proposed Changes" section or
"Public Interface"
>>> section. As
>>> >>>>> the
>>> >>>>>>>>> FLIP said, OperatorCoordinator is widely
used in many
>>> connectors.
>>> >>>>>> Though
>>> >>>>>>>> it
>>> >>>>>>>>> is still an @Internal API, I think it is worth
>>> mentioning the
>>> >>>>>>>>> change
>>> >>>>> in
>>> >>>>>>>> the
>>> >>>>>>>>> FLIP.
>>> >>>>>>>> Since OperatorCoordinator is an internal
API, it seems
>>> reasonable to
>>> >>>>>>>> explain it in the proposed change section.
The FLIP seems
>>> to have
>>> >>>>>>>> documented this in point 5 of the proposed
change section.
>>> >>>>>>>>
>>> >>>>>>>> BTW, if we think there are @internal
classes that are
>>> important
>>> >>>>>>>> enough
>>> >>>>>> to
>>> >>>>>>>> be added in the public interface section,
it might be
>>> useful to
>>> >>>>>> explicitly
>>> >>>>>>>> discuss this topic and document it in the
"*What are the
>>> "public
>>> >>>>>>>> interfaces" of the project*" in this
>>> >>>>>>>> <
>>> >>>>>>>>
>>> >>
>>>
>>
https://cwiki.apache.org/confluence/display/FLINK/Flink+Improvement+Proposals
>>> >>>>>>>> wiki.
>>> >>>>>>>>
>>> >>>>>>>>
>>> >>>>>>>>> Best,
>>> >>>>>>>>> Jark
>>> >>>>>>>>>
>>> >>>>>>>>>
>>> >>>>>>>>> On Mon, 26 Dec 2022 at 18:06, Hang Ruan
>>> <ruanhang1...@gmail.com>
>>> >>>>>> wrote:
>>> >>>>>>>>>> Hi, thanks for the feedback, Zhu Zhu and
Qingsheng.
>>> >>>>>>>>>> After combining everyone's comments, the main
concerns and
>>> >>>>>>>> corresponding
>>> >>>>>>>>>> adjustments are as follows.
>>> >>>>>>>>>>
>>> >>>>>>>>>> Q1: Common metrics are not quite useful.
>>> >>>>>>>>>> numEventsIn and numEventsOut counters will be
removed
>>> from the
>>> >>>>>>>>>> OperatorCoordinatorMetricGroup. These common
metrics do
>> not
>>> >>>>>>>>>> provide
>>> >>>>>>>>> enough
>>> >>>>>>>>>> information for users. The users are more
willing to
>>> get the
>>> >>>>>>>>>> number
>>> >>>>> of
>>> >>>>>>>>>> events of the specified type instead of the total
>>> number. And this
>>> >>>>>>>> metric
>>> >>>>>>>>>> is calculated differently. The implementation
could
>>> register the
>>> >>>>>> metric
>>> >>>>>>>>> by
>>> >>>>>>>>>> themselves.
>>> >>>>>>>>>>
>>> >>>>>>>>>> Q2: This FLIP is overly complicated.
>>> >>>>>>>>>> This FLIP will become concise after these
modifications.
>>> >>>>>>>>>> OperatorCoordinatorMetricGroup has already been
>>> introduced into
>>> >>>>> Flink
>>> >>>>>>>> by
>>> >>>>>>>>>> FLIP-179<
>>> >>>>>>>>>>
>>> >>>>>>>>>>
>>> >>
>>>
>>
https://cwiki.apache.org/confluence/display/FLINK/FLIP-179%3A+Expose+Standardized+Operator+Metrics
>>> >>>>>>>>>>> .
>>> >>>>>>>>>> And
>>> >>>>>>>>>> this FLIP will not change it. This FLIP only
provides a
>>> new metric
>>> >>>>>>>> option
>>> >>>>>>>>>> and a new metric group scope. The changes in
proposed
>>> changes
>>> >>>>> provide
>>> >>>>>>>> the
>>> >>>>>>>>>> details about the modifications for the internal
>>> classes, which
>>> >>>>> might
>>> >>>>>>>>> make
>>> >>>>>>>>>> it look complicated.
>>> >>>>>>>>>>
>>> >>>>>>>>>> Thanks for all the comments again. If there
are no further
>>> >>>>>>>>>> comments,
>>> >>>>>> we
>>> >>>>>>>>>> plan to start the voting thread this week.
>>> >>>>>>>>>>
>>> >>>>>>>>>> Best,
>>> >>>>>>>>>> Hang
>>> >>>>>>>>>>
>>> >>>>>>>>>> Qingsheng Ren <renqs...@gmail.com>
于2022年12月26日周一
>>> 16:48写道：
>>> >>>>>>>>>>
>>> >>>>>>>>>>
>>> >>>>>>>>>>> Thanks for the FLIP, Hang!
>>> >>>>>>>>>>>
>>> >>>>>>>>>>> This FLIP overall looks good to me. Actually
I share
>>> the same
>>> >>>>> concern
>>> >>>>>>>>>> with
>>> >>>>>>>>>>> Zhu that numEventsIn and numEventsOut
counters are not
>>> quite
>>> >>>>>>>>>>> useful
>>> >>>>>>>> to
>>> >>>>>>>>>> end
>>> >>>>>>>>>>> users. OperatorEvent is a quite low-level
abstraction,
>>> which
>>> >>>>> requires
>>> >>>>>>>>>>> instantialization in order to be practical to
users and
>>> >>>>>>>>>>> developers,
>>> >>>>>>>> so
>>> >>>>>>>>>>> maybe it's better to exclude them from the FLIP.
>>> >>>>>>>>>>>
>>> >>>>>>>>>>> Best,
>>> >>>>>>>>>>> Qingsheng
>>> >>>>>>>>>>> Ververica (Alibaba)
>>> >>>>>>>>>>>
>>> >>>>>>>>>>> On Mon, Dec 26, 2022 at 12:08 PM Zhu Zhu
>>> <reed...@gmail.com>
>>> >>>>> wrote:
>>> >>>>>>>>>>>> Hi Hang,
>>> >>>>>>>>>>>> I still see no strong reason why we need
>>> >>>>>>>>>>>> numEventsIn/numEventsOut
>>> >>>>>>>>>>> metrics.
>>> >>>>>>>>>>>> In the discussion in FLINK-29801, I can see
the same
>>> concern
>>> >>>>>>>>>>>> from
>>> >>>>>>>>>> others.
>>> >>>>>>>>>>>> So I prefer to exclude them from this FLIP
to avoid
>>> >>>>>>>>>>>> over-extending
>>> >>>>>>>>> the
>>> >>>>>>>>>>>> scope.
>>> >>>>>>>>>>>>
>>> >>>>>>>>>>>> Thanks,
>>> >>>>>>>>>>>> Zhu
>>> >>>>>>>>>>>>
>>> >>>>>>>>>>>> Hang Ruan <ruanhang1...@gmail.com>
于2022年12月23日周五
>>> >>>>>>>>>>>> 15:21写道：
>>> >>>>>>>>>>>>> Hi everyone,
>>> >>>>>>>>>>>>>
>>> >>>>>>>>>>>>> As for the Zhu Zhu's problem, I think we
should keep
>>> the common
>>> >>>>>>>>>>> metrics,
>>> >>>>>>>>>>>> which will help to observe incoming and outgoing
>>> events. What do
>>> >>>>>>>> you
>>> >>>>>>>>>>> think,
>>> >>>>>>>>>>>> @Zhu Zhu ?
>>> >>>>>>>>>>>>> And @Chesnay, are there any other issues
you are
>>> more concerned
>>> >>>>>>>>>> about?
>>> >>>>>>>>>>>> Looking forward to your reply.
>>> >>>>>>>>>>>>> Thanks for all the comments. If there are
no further
>>> >>>>>>>>>>>>> comments, we
>>> >>>>>>>>>> plan
>>> >>>>>>>>>>>> to start the voting thread next week.
>>> >>>>>>>>>>>>> Best,
>>> >>>>>>>>>>>>> Hang
>>> >>>>>>>>>>>>>
>>> >>>>>>>>>>>>> Hang Ruan <ruanhang1...@gmail.com>
于2022年12月15日周四
>>> >>>>>>>>>>>>> 16:49写道：
>>> >>>>>>>>>>>>>> Hi, Zhu Zhu,
>>> >>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>> Thanks for your feedback!
>>> >>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>> The OperatorCoordinator implementations are
>>> different. And
>>> >>>>>>>>>>>>>> their
>>> >>>>>>>>>>>> metrics are much different too. We try to
find the
>> common
>>> >>>>>>>>>>>> metrics
>>> >>>>>>>> and
>>> >>>>>>>>>> put
>>> >>>>>>>>>>>> them in the OperatorCoordinatorMetricGroup.
If most
>>> developers
>>> >>>>>>>> think
>>> >>>>>>>>> we
>>> >>>>>>>>>>> do
>>> >>>>>>>>>>>> not need these common metrics, removing the
common
>>> metrics is
>>> >>>>>>>>>>>> also
>>> >>>>>>>>>>>> acceptable.
>>> >>>>>>>>>>>>>> Best,
>>> >>>>>>>>>>>>>> Hang
>>> >>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>> Zhu Zhu <reed...@gmail.com>
于2022年12月14日周三
>>> 22:09写道：
>>> >>>>>>>>>>>>>>> Hi Hang & MengYue,
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> Thanks for creating this FLIP!
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> I think it is very useful, mainly in two
aspects:
>>> >>>>>>>>>>>>>>> 1. Enables OperatorCoordinators to
register metrics.
>>> >>>>>>>>>>>>>>> Currently
>>> >>>>>>>>>>>>>>> the coordinators has no way to do this.
And operator
>>> >>>>>>>> coordinator
>>> >>>>>>>>>>>>>>> metric group further enables the
SplitEnumerator
>>> to have
>>> >>>>>>>>>>>>>>> access
>>> >>>>>>>>>>>>>>> to a registered metric group (via the
existing public
>>> >>>>>>>>>>>>>>> interface
>>> >>>>>>>>>>>>>>> SplitEnumeratorContext#metricGroup()),
which is
>>> null at the
>>> >>>>>>>>> moment.
>>> >>>>>>>>>>>>>>> 2. Defines the scope of operator coordinator
>>> metrics. A clear
>>> >>>>>>>>>>>> definition
>>> >>>>>>>>>>>>>>> makes it easy for users to find their wanted
>>> metrics. The
>>> >>>>>>>>>> definition
>>> >>>>>>>>>>>>>>> also helps to avoid conflicts of metrics from
>> multiple
>>> >>>>>>>>>>>> OperatorCoordinators
>>> >>>>>>>>>>>>>>> of the same kind. E.g. each
SourceCoordinator may
>>> have its
>>> >>>>>>>>>>>>>>> own
>>> >>>>>>>>>>>>>>> numSourceSplits metric, these metrics
should not
>>> be directly
>>> >>>>>>>>>>> registered
>>> >>>>>>>>>>>>>>> to the job metric group.
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> What I'm a bit concerned is the necessity
of the
>>> introduced
>>> >>>>>>>>> common
>>> >>>>>>>>>>>> metrics
>>> >>>>>>>>>>>>>>> numEventsInCounter & numEventsOutCounter.
If there
>>> any case
>>> >>>>>>>> which
>>> >>>>>>>>>>>> strongly
>>> >>>>>>>>>>>>>>> requires them?
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> Regarding the concerns of Chesnay,
>>> >>>>>>>>>>>>>>>> A dedicated coordinator MG implementation is
>> overkill
>>> >>>>>>>>>>>>>>> Directly using the job metric group can
result in
>>> metric
>>> >>>>>>>>> conflicts,
>>> >>>>>>>>>>> as
>>> >>>>>>>>>>>> mentioned
>>> >>>>>>>>>>>>>>> in above #2.
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> Thanks,
>>> >>>>>>>>>>>>>>> Zhu
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>> Dong Lin <lindon...@gmail.com>
于2022年12月10日周六
>>> >>>>>>>>>>>>>>> 14:16写道：
>>> >>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>> Hi Chesney,
>>> >>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>> Just to double check with you,
>>> >>>>>>>>>>>>>>>> OperatorCoordinatorMetricGroup
>>> >>>>>>>>>>>> (annotated as
>>> >>>>>>>>>>>>>>>> @PublicEvolving) has already been
introduced into
>>> Flink by
>>> >>>>>>>>>> FLIP-179
>>> >>>>>>>>>>>>>>>> <
>>> >>
>>>
>>
https://cwiki.apache.org/confluence/display/FLINK/FLIP-179%3A+Expose+Standardized+Operator+Metrics
>>> >>>>>>>>>>>>> .
>>> >>>>>>>>>>>>>>>> And that FLIP has got you +1.. Do you
mean we
>>> should remove
>>> >>>>>>>>> this
>>> >>>>>>>>>>>>>>>> OperatorCoordinatorMetricGroup?
>>> >>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>> Regards,
>>> >>>>>>>>>>>>>>>> Dong
>>> >>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>> On Sat, Dec 10, 2022 at 1:33 AM Chesnay
Schepler <
>>> >>>>>>>>>>> ches...@apache.org>
>>> >>>>>>>>>>>> wrote:
>>> >>>>>>>>>>>>>>>>> As a whole I feel like this FLIP is overly
>>> complicated. A
>>> >>>>>>>>>>> dedicated
>>> >>>>>>>>>>>>>>>>> coordinator MG implementation is
overkill; it
>>> could just
>>> >>>>>>>>> re-use
>>> >>>>>>>>>>> the
>>> >>>>>>>>>>>>>>>>> existing Task/OperatorMGs to create the
same
>>> structure we
>>> >>>>>>>>> have
>>> >>>>>>>>>> on
>>> >>>>>>>>>>>> TMs,
>>> >>>>>>>>>>>>>>>>> similar to what we did with the Job MG.
>>> >>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>> However, I'm not convinced that this is
required
>>> anyway,
>>> >>>>>>>>>> because
>>> >>>>>>>>>>>> all the
>>> >>>>>>>>>>>>>>>>> example metrics you listed can be
implemented on
>>> the TM
>>> >>>>>>>> side
>>> >>>>>>>>> +
>>> >>>>>>>>>>>>>>>>> aggregating them in the external
metrics backend.
>>> >>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>> Since I'm on holidays soon, just so no
one tries
>>> to pull a
>>> >>>>>>>>> fast
>>> >>>>>>>>>>>> one on
>>> >>>>>>>>>>>>>>>>> me, if this were to go to a vote as-is
I'd be
>>> against it.
>>> >>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>> On 09/12/2022 15:30, Dong Lin wrote:
>>> >>>>>>>>>>>>>>>>>> Hi Hang,
>>> >>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>> Thanks for the FLIP! The FLIP looks
good and it
>>> is pretty
>>> >>>>>>>>>>>> informative.
>>> >>>>>>>>>>>>>>>>>> I have just two minor comments
regarding names:
>>> >>>>>>>>>>>>>>>>>> - Would it be useful to rename the
config key as
>>> >>>>>>>>>>>>>>>>>>
*metrics.scope.jm.job.operator-coordinator* for
>>> >>>>>>>> consistency
>>> >>>>>>>>>>> with
>>> >>>>>>>>>>>>>>>>>> *metrics.scope.jm.job
>>> >>>>>>>>>>>>>>>>>> *(which is not named as *jm-job)?
>>> >>>>>>>>>>>>>>>>>> - Maybe rename the variable as
>>> >>>>>>>>>>> SCOPE_NAMING_OPERATOR_COORDINATOR
>>> >>>>>>>>>>>> for
>>> >>>>>>>>>>>>>>>>>> simplicity and consistency with
>>> SCOPE_NAMING_OPERATOR
>>> >>>>>>>>> (which
>>> >>>>>>>>>> is
>>> >>>>>>>>>>>> not named
>>> >>>>>>>>>>>>>>>>>> as SCOPE_NAMING_TM_JOB_OPERATOR)?
>>> >>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>> Cheers,
>>> >>>>>>>>>>>>>>>>>> Dong
>>> >>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>> On Thu, Dec 8, 2022 at 3:28 PM Hang Ruan <
>>> >>>>>>>>>>> ruanhang1...@gmail.com>
>>> >>>>>>>>>>>> wrote:
>>> >>>>>>>>>>>>>>>>>>> Hi all,
>>> >>>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>> MengYue and I created FLIP-274[1]
Introduce
>>> metric group
>>> >>>>>>>>> for
>>> >>>>>>>>>>>>>>>>>>> OperatorCoordinator.
OperatorCoordinator is the
>>> >>>>>>>>> coordinator
>>> >>>>>>>>>>> for
>>> >>>>>>>>>>>> runtime
>>> >>>>>>>>>>>>>>>>>>> operators and running on Job Manager. The
>>> coordination
>>> >>>>>>>>>>>> mechanism is
>>> >>>>>>>>>>>>>>>>>>> operator events between
OperatorCoordinator
>>> and its all
>>> >>>>>>>>>>>> operators, the
>>> >>>>>>>>>>>>>>>>>>> coordination is more and more using
in Flink, for
>>> >>>>>>>> example
>>> >>>>>>>>>> many
>>> >>>>>>>>>>>> Sources
>>> >>>>>>>>>>>>>>>>> and
>>> >>>>>>>>>>>>>>>>>>> Sinks depend on the mechanism to
assign splits
>> and
>>> >>>>>>>>>> coordinate
>>> >>>>>>>>>>>> commits to
>>> >>>>>>>>>>>>>>>>>>> external systems. The
OperatorCoordinator is
>>> widely
>>> >>>>>>>> using
>>> >>>>>>>>> in
>>> >>>>>>>>>>>> flink kafka
>>> >>>>>>>>>>>>>>>>>>> connector, flink pulsar connector,
flink cdc
>>> connector,
>>> >>>>>>>>>> flink
>>> >>>>>>>>>>>> hudi
>>> >>>>>>>>>>>>>>>>>>> connector and so on.
>>> >>>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>> But there is not a suitable metric
group scope
>>> for the
>>> >>>>>>>>>>>>>>>>> OperatorCoordinator
>>> >>>>>>>>>>>>>>>>>>> and not an implementation for the
interface
>>> >>>>>>>>>>>>>>>>> OperatorCoordinatorMetricGroup.
>>> >>>>>>>>>>>>>>>>>>> These metrics in OperatorCoordinator
could be
>>> how many
>>> >>>>>>>>>>>> splits/partitions
>>> >>>>>>>>>>>>>>>>>>> have been assigned to source readers,
how many
>>> files
>>> >>>>>>>> have
>>> >>>>>>>>>> been
>>> >>>>>>>>>>>> written
>>> >>>>>>>>>>>>>>>>> out
>>> >>>>>>>>>>>>>>>>>>> by sink writers, these metrics not
only help
>>> users to
>>> >>>>>>>> know
>>> >>>>>>>>>> the
>>> >>>>>>>>>>>> job
>>> >>>>>>>>>>>>>>>>> progress
>>> >>>>>>>>>>>>>>>>>>> but also make big job maintaining
easier. Thus we
>>> >>>>>>>> propose
>>> >>>>>>>>>> the
>>> >>>>>>>>>>>> FLIP-274
>>> >>>>>>>>>>>>>>>>> to
>>> >>>>>>>>>>>>>>>>>>> introduce a new metric group scope for
>>> >>>>>>>> OperatorCoordinator
>>> >>>>>>>>>> and
>>> >>>>>>>>>>>> provide
>>> >>>>>>>>>>>>>>>>> an
>>> >>>>>>>>>>>>>>>>>>> internal implementation for
>>> >>>>>>>>> OperatorCoordinatorMetricGroup.
>>> >>>>>>>>>>>>>>>>>>> Could you help review this FLIP when
you get
>>> time? Any
>>> >>>>>>>>>>> feedback
>>> >>>>>>>>>>>> is
>>> >>>>>>>>>>>>>>>>>>> appreciated!
>>> >>>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>> Best,
>>> >>>>>>>>>>>>>>>>>>> Hang
>>> >>>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>> [1]
>>> >>>>>>>>>>>>>>>>>>>
>>> >>>>>>>>>>>>>>>>>>>
>>> >>
>>>
>>
https://cwiki.apache.org/confluence/display/FLINK/FLIP-274%3A+Introduce+metric+group+for+OperatorCoordinator
>>> >>
>>>
