Hi lajith,
Yes I like the simplicity of the current proposal.
Hi Gyula,
The next stage is to assign a Flip number and move the content of the google
doc into the flip wiki. Unfortunately, as we are not committers, we are not
authorized to do either of these activities. Are you able to copy this over or
get another committer to do this please; so we can get this moving.
Kind regards, David.
From: Lajith Koova <[email protected]>
Date: Monday, 14 October 2024 at 08:52
To: [email protected] <[email protected]>
Subject: [EXTERNAL] Re: [DISCUSS] FLIP-XXX Add K8S conditions to Flink CRD
Thank you all for the valuable feedback .
Following the procedure outlined on the Flink Improvement Proposal
Confluence page [1], we kindly ask the PMC/Committers to transfer the
content from the Add K8S conditions to CRD's Status [2] and assign a
FLIP Number for us, which we will use for voting.
[1]
https://cwiki.apache.org/confluence/display/FLINK/Flink+Improvement+Proposals#FlinkImprovementProposals-Process
[2]
https://docs.google.com/document/d/12wlJCL_Vq2KZnABzK7OR7gAd1jZMmo0MxgXQXqtWODs/edit?tab=t.0
Thanks
Lajith
On Mon, Sep 23, 2024 at 11:54 PM Gyula Fóra <[email protected]> wrote:
> Hey!
>
> I think the proposal is now simple enough :
> - Running condition for Applications / SessionJobs
> - Ready condition for Session clusters
>
> I think we should formalize this into a Flip page and start the vote on
> this from my side.
> The next step to consider is having an independent condition that captures
> the upgrade process itself (if a resource is fully upgraded / reconciled)
>
> Cheers,
> Gyula
>
> On Mon, Sep 23, 2024 at 12:16 PM David Radley <[email protected]>
> wrote:
>
> > Hi Lajith,
> > The updated document is much more detailed and looks good. As you say the
> > only situation that is not handled currently is when there are multiple
> > Flink jobs running in Application Mode.
> >
> > As discussed , you are looking to test this situation so we know how it
> > will perform.
> >
> > When you say “During transition of Job state, there will be only one
> > condition for the
> > Flink Deployment in application mode.”. I am not sure I understand.
> >
> > * I thought we have 1 condition per Flink job state, so I assume we
> > have one true condition and potentially other historical false ones.
> > * When you say during transition, are you thinking of some small time
> > window between states. I am not sure what you are saying here.
> >
> >
> > Kind regards , David
> >
> >
> > From: Lajith Koova <[email protected]>
> > Date: Wednesday, 11 September 2024 at 03:01
> > To: [email protected] <[email protected]>
> > Subject: [EXTERNAL] Re: [DISCUSS] FLIP-XXX Add K8S conditions to Flink
> CRD
> > Hi,
> >
> > Here is the updated Proposal doc
> > <
> >
> https://docs.google.com/document/d/12wlJCL_Vq2KZnABzK7OR7gAd1jZMmo0MxgXQXqtWODs/edit#heading=h.cz8x5nsncuwb
> > >
> > .
> >
> > *Summary : *
> >
> > Session Mode:
> >
> > Status conditions will be populated with status of Job manager.
> >
> > Application Mode:
> >
> > 1. In application mode , status conditions will be populated with status
> of
> > Job running in the cluster.
> >
> > 2. Each Flink Job state will have one condition associated with.
> >
> > 3. During transition of Job state, there will be only one condition for
> the
> > Flink Deployment in application mode.
> >
> > 4. If there are multiple Jobs in application, how to handle them in
> > populating the condition status?. does condition status should contain
> > information about multiple jobs?.
> >
> > Please let me know your inputs and suggestions.
> >
> >
> > Regards
> >
> > Lajith
> >
> >
> > On Fri, Jun 7, 2024 at 10:25 AM Lajith Koova <[email protected]>
> wrote:
> >
> > > Thank you Gyula for the feedback.
> > >
> > > From the above proposed conditions, so will be having two conditions
> as
> > > below
> > >
> > > status:
> > > conditions:
> > > - type: JobReady
> > > message: The Job is running
> > > reason: running
> > > status: 'True'
> > > lastTransitionTime: ''
> > > - type: ReconciliationSucceed
> > > message: The resource deployment is considered to be stable and won’t
> be
> > > rolled back
> > > reason: stable
> > > status: 'True'
> > > lastTransitionTime: ''
> > >
> > >
> > > Condition JobReady is derived from JobStatus and Condition
> > ReconciliationSucceed
> > > derived from LifecycleState.
> > >
> > > Please correct me if I missed anything.
> > >
> > >
> > > Thanks
> > > Lajith K
> > >
> > > On Thu, May 30, 2024 at 2:23 PM Gyula Fóra <[email protected]>
> wrote:
> > >
> > >> David,
> > >>
> > >> The problem is exactly that ResourceLifecycleStates do not correspond
> to
> > >> specific Job statuses (JobReady condition) in most cases. Let me give
> > you
> > >> a
> > >> concrete example:
> > >>
> > >> ResourceLifecycleState.STABLE means that app/job defined in the spec
> has
> > >> been successfully deployed and was observed running, and this spec is
> > now
> > >> considered to be stable (won't be rolled back). Once a resource
> > >> (FlinkDeployment) reached STABLE state, it won't change unless the
> user
> > >> changes the spec. At the same time, this doesn't really say anything
> > about
> > >> job health/readiness at any given future time. 10 minutes later the
> job
> > >> can
> > >> go in an unrecoverable failure loop and never reach a running status,
> > the
> > >> ResourceLifecycleState will remain STABLE.
> > >>
> > >> This is actually not a problem with the ResourceLifecycleState but
> more
> > >> with the understanding of it. It's called ResourceLifecycleState and
> not
> > >> JobState exactly because it refers to the upgrade/rollback/suspend etc
> > >> lifecycle of the FlinkDeployment/FlinkSessionJob resource and not the
> > >> underlying flink job itself.
> > >>
> > >> But this is a crucial detail here that we need to consider otherwise
> the
> > >> "Ready" condition that we may create will be practically useless.
> > >>
> > >> This is the reason why @[email protected] <[email protected]> and
> > >> I suggest separating this to at least 2 independent conditions. One
> > could
> > >> be the UpgradeCompleted/ReconciliationCompleted or something along
> these
> > >> lines computed based on LifecycleState (as described in your proposal
> > but
> > >> with a different name). The other should be JobReady which could
> > initially
> > >> work based on the JobStatus.state field but ideally would be user
> > >> configurable ready condition such as (job running at least 10 minutes,
> > >> running and have taken checkpoints etcetc).
> > >>
> > >> These 2 conditions should be enough to start with and would actually
> > >> provide a tangible value to users. We can probably leave out
> > ClusterReady
> > >> on a second thought.
> > >>
> > >> Cheers,
> > >> Gyula
> > >>
> > >>
> > >> On Wed, May 29, 2024 at 5:16 PM David Radley <[email protected]
> >
> > >> wrote:
> > >>
> > >> > Hi Gyula,
> > >> > Thank you for the quick response and confirmation we need a Flip. I
> am
> > >> not
> > >> > an expert at K8s, Lajith will answer in more detail. Some questions
> I
> > >> had
> > >> > anyway:
> > >> >
> > >> > I assume each of the ResourceLifecycleState do have a corresponding
> > >> > jobReady status. You point out some mistakes in the table, for
> example
> > >> that
> > >> > STABLE should be NotReady; thankyou. If we put a reason mentioning
> > the
> > >> > stable state, this would help us understand the jobStatus.
> > >> >
> > >> > I guess the jobReady is one perspective that we know is useful (with
> > >> > corrected mappings from ResourceLifecycleState and with reasons).
> > Can I
> > >> > check that the 2 proposed conditions would also be useful
> additions?
> > I
> > >> > assume that in your proposal when jobReady is true, then
> > >> UpgradeCompleted
> > >> > condition would not be present and ClusterReady would always be
> true?
> > I
> > >> > know conditions do not need to be orthogonal, but I wanted to check
> > what
> > >> > your thoughts are.
> > >> >
> > >> > Kind regards, David.
> > >> >
> > >> >
> > >> >
> > >> >
> > >> > From: Gyula Fóra <[email protected]>
> > >> > Date: Wednesday, 29 May 2024 at 15:28
> > >> > To: [email protected] <[email protected]>
> > >> > Cc: [email protected] <[email protected]>
> > >> > Subject: [EXTERNAL] Re: [DISCUSS] FLIP-XXX Add K8S conditions to
> Flink
> > >> CRD
> > >> > Hi David!
> > >> >
> > >> > This change definitely warrants a FLIP even if the code change is
> not
> > >> huge,
> > >> > there are quite some implications going forward.
> > >> >
> > >> > Looping in @[email protected] <[email protected]> for this
> > >> discussion.
> > >> >
> > >> > I have some questions / suggestions regarding the condition's
> meaning
> > >> and
> > >> > naming.
> > >> >
> > >> > In your proposal you have:
> > >> > - Ready (True/False) -> This condition is intended for resources
> > which
> > >> are
> > >> > fully ready and operational
> > >> > - Error (True) -> This condition can be used in scenarios where any
> > >> > exception/error during resource reconcile process
> > >> >
> > >> > The problem with the above is that the implementation does not well
> > >> reflect
> > >> > this. ResourceLifecycleState STABLE/ROLLED_BACK does not actually
> mean
> > >> the
> > >> > job is running, it just means that the resource is fully reconciled
> > and
> > >> it
> > >> > will not be rolled back (so the current pending upgrade is
> completed).
> > >> This
> > >> > is mainly a fault of the ResourceLifecycleState as it doesn't
> capture
> > >> the
> > >> > job status but one could argue that it was "designed" this way.
> > >> >
> > >> > I think we should probably have more condition types to capture the
> > >> > difference:
> > >> > - JobReady (True/False) -> Flink job is running (Basically job
> status
> > >> but
> > >> > with transition time)
> > >> > - ClusterReady (True/False) -> Session / Application cluster is
> > >> deployed
> > >> > (Basically JM deployment status but with transition time)
> > >> > - UpgradeCompleted (True/False) -> Similar to what you call Ready
> now
> > >> > which should correspond to the STABLE/ROLLED_BACK states and mostly
> > >> tracks
> > >> > in-progress CR updates
> > >> >
> > >> > This is my best idea at the moment, not great as it feels a little
> > >> > redundant with the current status fields. But maybe thats not a
> > problem
> > >> or
> > >> > a way to eliminate the old fields later?
> > >> >
> > >> > I am not so sure of the Error status and what this means in
> practice.
> > >> Why
> > >> > do we want to track the last error in 2 places? It's already in the
> > >> status.
> > >> >
> > >> > What do you think?
> > >> > Gyula
> > >> >
> > >> > On Wed, May 29, 2024 at 3:55 PM David Radley <
> [email protected]
> > >
> > >> > wrote:
> > >> >
> > >> > > Hi,
> > >> > > Thanks Lajith for raising this discussion thread under the Flip
> > title.
> > >> > >
> > >> > > To summarise the concerns from the other discussion thread.
> > >> > >
> > >> > > “
> > >> > > - I echo Gyula that including some examples and further
> explanations
> > >> > might
> > >> > > ease reader's work. With the current version, the FLIP is a bit
> hard
> > >> to
> > >> > > follow. - Will the usage of Conditions be enabled by default? Or
> > will
> > >> > there
> > >> > > be any disadvantages for Flink users? If Conditions with the same
> > type
> > >> > > already exist in the Status Conditions
> > >> > >
> > >> > > - Do you think we should have clear rules about handling rules for
> > how
> > >> > > these Conditions should be managed, especially when multiple
> > >> Conditions
> > >> > of
> > >> > > the same type are present? For example, resource has multiple
> causes
> > >> for
> > >> > > the same condition (e.g., Error due to network and Error due to
> > I/O).
> > >> > Then,
> > >> > > overriding the old condition with the new one is not the best
> > approach
> > >> > no?
> > >> > > Please correct me if I misunderstood.
> > >> > > “
> > >> > >
> > >> > > I see the Google doc link has been reformatted to match the Flip
> > >> > template.
> > >> > >
> > >> > > To explicitly answer the questions from Jeyhun and Gyula:
> > >> > > - “Will the usage of Conditions be enabled by default?” Yes, but
> > this
> > >> is
> > >> > > just making the status content useful, whereas before it was not
> > >> useful.
> > >> > > - in terms of examples, I am not sure what you would like to see,
> > the
> > >> > > table Lajith provided shows the status for various
> > >> > ResourceLifecycleStates.
> > >> > > How the operator gets into these states is the current behaviour.
> > The
> > >> > > change just shows the appropriate corresponding high level status
> –
> > >> that
> > >> > > could be shown on the User Interfaces.
> > >> > > - “will there be any disadvantages for Flink users?” None , there
> is
> > >> just
> > >> > > more information in the status, without this it is more difficult
> to
> > >> work
> > >> > > out the status of the job.
> > >> > > - Multiple conditions question. The status is showing whether the
> > job
> > >> is
> > >> > > ready or not, so as long as the last condition is the one that is
> > >> shown -
> > >> > > all is as expected. I don’t think this needs rules for precedence
> > and
> > >> the
> > >> > > like.
> > >> > > - The condition’s Reason is going to be more specific.
> > >> > >
> > >> > > Gyula and Jeyhun, is the google doc clear enough for you now? Do
> you
> > >> feel
> > >> > > you feedback has been addressed? Lajith and I are happy to provide
> > >> more
> > >> > > details.
> > >> > >
> > >> > > I wonder whether this change is big enough to warrant a Flip, as
> it
> > >> is so
> > >> > > small. We could do this in an issue. WDYT?
> > >> > >
> > >> > > Kind regards, David.
> > >> > >
> > >> > >
> > >> > > From: Lajith Koova <[email protected]>
> > >> > > Date: Wednesday, 29 May 2024 at 13:41
> > >> > > To: [email protected] <[email protected]>
> > >> > > Subject: [EXTERNAL] [DISCUSS] FLIP-XXX Add K8S conditions to Flink
> > CRD
> > >> > > Hello ,
> > >> > >
> > >> > >
> > >> > > Discussion thread here:
> > >> > > https://lists.apache.org/thread/dvy8w17pyjv68c3t962w49frl9odoz4z
> > to
> > >> > > discuss a proposal to add Conditions field in the CR status of
> Flink
> > >> > > Deployment and FlinkSessionJob.
> > >> > >
> > >> > >
> > >> > > Note : Starting this new thread as discussion thread title has
> been
> > >> > > modified to follow the FLIP process.
> > >> > >
> > >> > >
> > >> > > Thank you.
> > >> > >
> > >> > > Unless otherwise stated above:
> > >> > >
> > >> > > IBM United Kingdom Limited
> > >> > > Registered in England and Wales with number 741598
> > >> > > Registered office: PO Box 41, North Harbour, Portsmouth, Hants.
> PO6
> > >> 3AU
> > >> > >
> > >> >
> > >> > Unless otherwise stated above:
> > >> >
> > >> > IBM United Kingdom Limited
> > >> > Registered in England and Wales with number 741598
> > >> > Registered office: PO Box 41, North Harbour, Portsmouth, Hants. PO6
> > 3AU
> > >> >
> > >>
> > >
> >
> > Unless otherwise stated above:
> >
> > IBM United Kingdom Limited
> > Registered in England and Wales with number 741598
> > Registered office: PO Box 41, North Harbour, Portsmouth, Hants. PO6 3AU
> >
>
Unless otherwise stated above:
IBM United Kingdom Limited
Registered in England and Wales with number 741598
Registered office: Building C, IBM Hursley Office, Hursley Park Road,
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