TsukiokaKogane commented on PR #54071:
URL: https://github.com/apache/doris/pull/54071#issuecomment-3311209064
> when balance a tablet with special tag T and medium M, it invoke three
replicas on 3 BE:
>
> 1. On a high load be BE1, migrate out a replica RA, its action is
delete replica RA;
> 2. On a low load be BE2, migrate in a new replica RB, its action is copy
a new replica;
> 3. chose any idle be BE3, use its replica RC as the copy source for
replica RB in 2.
>
> for BE1 and BE2, their tag = T, their medium = M, and
clusterStat.isMoreBalanced is just comparing their load.
>
> for BE3 as the copy source, its tag is unknown and no need to be T, it's
just use as the copy source, it can be any BE.
>
> This PR is let BE3's tag must be T, but it shouldn't do so.
I don't see it as much of a problem here, it may be just a bit slower. In
my opinion, currently the balance logic originated from without location tag,
is only fit for balance within the same location tag **as it's hard to evaluate
is more balanced across different location tags**, otherwise we may have to
refractor the whole balance logic
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
