Fair points. I retract the yaml suggestion and +1 to go with the
correctness route.

Em ter., 24 de nov. de 2020 às 11:13, Benjamin Lerer <
benjamin.le...@datastax.com> escreveu:

> Paulo, what you propose with the yaml seems different from default to
> *correctness*. It means to me that we are forcing the user to choose
> between *correctness *and *performance*. Most of us have a good
> understanding of the problem and it is a hard choice for us. I imagine that
> most of the users do not fully understand LWTs and will not know what to
> choose. Some might not even use LWTs and will suddenly be forced to make a
> choice that they do not understand. It does not feel right to me to push
> them to make that choice.
>
> I also agree with Benedict and Mick that it is a risky thing to do.
>
> something that can bring a cluster down upon an unprepared user.
>
>
> I do not think that it will be the case (feel free to correct me Benedict).
> The impact will probably be an increase in the number of write/read
> timeouts for the LWTs read/writes. For a heavy load that would cause the
> services depending on those queries to become unreliable. On the other hand
> the impact of the current problem is that we can hit some correctness issue
> without even knowing it.
>
> We need to choose between two imperfect solutions and we have some
> difficulties to agree on which one to choose.
>
> Benedict suggested that Sylvain and I made the choice. Sylvain did not want
> to make the final call.
> I chose correctness. If it is a problem and people prefer to vote. It is
> perfectly fine for me too :-)
>
> I just want us to move forward.
>
>
>
> On Tue, Nov 24, 2020 at 12:52 PM Mick Semb Wever <m...@apache.org> wrote:
>
> > > I think the keyword there is "normally" - if we can't say _certainly_,
> > > then this is probably an unsafe change to make.
> > >
> > > I can imagine any number of hacky upgrade processes that would be
> > > dangerous with this change.
> > >
> >
> >
> > I agree. We just don't know what users are doing, this is risky.
> >
> > IMO the same applies to a performance degradation, i.e. something that
> can
> > bring a cluster down upon an unprepared user. Despite our best efforts
> with
> > NEWS.txt we should still look after such users. IMHO the imperfection of
> > LWTs on past branches we have to carry. I'm well aware this is easier
> said
> > than done, even for far simpler changes. Having the flag there to switch
> to
> > "correct LWT" is still a huge win for users.
> >
>

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