Re: [DISCUSS] KIP-926: introducing acks=min.insync.replicas config

[67]

Hi Luke,

It's a good point that add this config and get better P99 latency, but is this 
changing the meaning of "in sync replicas"? consider a situation with 
"replica=3 acks=2", when two broker fail and left only the broker that does't 
have the message, it is in sync, so will be elected as leader, will it cause a 
NOT NOTICED lost of acked messages?


qiangLiu







在2023年05月10 12时58分，"Ismael Juma"写道：

Hi Luke,

As discussed in the other KIP, there are some subtleties when it comes to
the semantics of the system if we don't wait for all members of the isr
before we ack. I don't understand why you say the leader election question
is out of scope - it seems to be a core aspect to me.

Ismael


On Wed, May 10, 2023, 8:50 AM Luke Chen  wrote:

> Hi Ismael,
>
> No, I didn't know about this similar KIP! I hope I've known that so that I
> don't need to spend time to write it again! :(
> I checked the KIP and all the discussions (here
> ). I
> think the consensus is that adding a client config to `acks=quorum` is
> fine.
> This comment
>  from
> Guozhang pretty much concluded what I'm trying to do.
>
>
>
>
>
>
>
>
> *1. Add one more value to client-side acks config:   0: no acks needed at
> all.   1: ack from the leader.   all: ack from ALL the ISR replicas
>  quorum: this is the new value, it requires ack from enough number of ISR
> replicas no smaller than majority of the replicas AND no smaller
> than{min.isr}.2. Clarify in the docs that if a user wants to tolerate X
> failures, she needs to set client acks=all or acks=quorum (better tail
> latency than "all") with broker {min.sir} to be X+1; however, "all" is not
> necessarily stronger than "quorum".*
>
> Concerns from KIP-250 are:
> 1. Introducing a new leader LEO based election method. This is not clear in
> the KIP-250 and needs more discussion
> 2. The KIP-250 also tried to optimize the consumer latency to read messages
> beyond high watermark, which also has some discussion about how to achieve
> that, and no conclusion
>
> Both of the above 2 concerns are out of the scope of my current KIP.
> So, I think it's good to provide this `acks=quorum` or
> `acks=min.insync.replicas` option to users to give them another choice.
>
>
> Thank you.
> Luke
>
>
> On Wed, May 10, 2023 at 8:54 AM Ismael Juma  wrote:
>
> > Hi Luke,
> >
> > Are you aware of
> >
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-250+Add+Support+for+Quorum-based+Producer+Acknowledgment
> > ?
> >
> > Ismael
> >
> > On Tue, May 9, 2023 at 10:14 PM Luke Chen  wrote:
> >
> > > Hi all,
> > >
> > > I'd like to start a discussion for the KIP-926: introducing
> > > acks=min.insync.replicas config. This KIP is to introduce
> > > `acks=min.insync.replicas` config value in producer, to improve the
> write
> > > throughput and still guarantee high durability.
> > >
> > > Please check the link for more detail:
> > >
> > >
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-926%3A+introducing+acks%3Dmin.insync.replicas+config
> > >
> > > Any feedback is welcome.
> > >
> > > Thank you.
> > > Luke
> > >
> >
>

KAFKA-12889 pull request review request

[67]

hi kafka devlopers.

I have created a jira KAFKA-12889 and a pull requst 10818 for fix log cleaner 
may left empty segments about every 2^31 messages.
It has been about two weeks since the pr, but not got any review. ping some 
commiter on github but still no response.
so, can some one review this or tell me what to do next to continue this 
contribution


best wishes and thanks.


qiang

Create KIP permission request

[67]

hi there

I have a proposal which may change behavior of kafka-server-stop.sh， this 
script kill all instance on the host without any confirm,  someone may just 
want to kill the single one, so maybe a confirm when find multy instance is 
more safer.
already create a issue(https://issues.apache.org/jira/browse/KAFKA-9709) 
and pull request(https://github.com/apache/kafka/pull/8275), more detail can be 
found there.
a KIP is necessary too, so request for the permission to do so, my wiki 
id(login name) is 67


not native english speedker, forgive me if I have language problems.


best wishes



qiang liu