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https://issues.apache.org/jira/browse/FLINK-21321?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17453778#comment-17453778
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Yuan Mei edited comment on FLINK-21321 at 12/6/21, 4:50 AM:
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Hey [~legojoey17], thanks for contributing! 

Just a kindly ask that whether you are still interested in working on this 
issue?

We are planning to include this `delete range` optimization into Flink Release 
1.15 (this release cycle) after rocksdb version was upgraded (in 1.14).

And a few other optimizations/tests depend on your PR as well.

Would you be able to continue on this effort within the next month? Code freeze 
for 1.15 release is in Feb.


was (Author: ym):
Hey [~legojoey17], thanks for contributing! 

Just a kindly ask that whether you are still interested in working on this 
issue?

We are planning to include this `delete range` optimization into Flink Release 
1.15 (this release cycle) after rocksdb version was upgraded (in 1.14).

And a few other optimizations/tests depend on this as well.

Would you be able to continue on this effort in the next month? Code freeze for 
1.15 release is in Feb.

> Change RocksDB incremental checkpoint re-scaling to use deleteRange
> -------------------------------------------------------------------
>
>                 Key: FLINK-21321
>                 URL: https://issues.apache.org/jira/browse/FLINK-21321
>             Project: Flink
>          Issue Type: Improvement
>          Components: Runtime / State Backends
>            Reporter: Joey Pereira
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 1.15.0
>
>
> InĀ FLINK-8790, it was suggested to use RocksDB's {{deleteRange}} API to more 
> efficiently clip the databases for the desired target group.
> During the PR for that ticket, 
> [#5582|https://github.com/apache/flink/pull/5582], the change did not end up 
> using the {{deleteRange}} method  as it was an experimental feature in 
> RocksDB.
> At this point {{deleteRange}} is in a far less experimental state now but I 
> believe is still formally "experimental". It is heavily by many others like 
> CockroachDB and TiKV and they have teased out several bugs in complex 
> interactions over the years.
> For certain re-scaling situations where restores trigger 
> {{restoreWithScaling}} and the DB clipping logic, this would likely reduce an 
> O[n] operation (N = state size/records) to O(1). For large state apps, this 
> would potentially represent a non-trivial amount of time spent for 
> re-scaling. In the case of my workplace, we have an operator with 100s of 
> billions of records in state and re-scaling was taking a long time (>>30min, 
> but it has been awhile since doing it).



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