TanYuxin-tyx opened a new pull request, #20315:
URL: https://github.com/apache/flink/pull/20315

   <!--
   *Thank you very much for contributing to Apache Flink - we are happy that 
you want to help us improve Flink. To help the community review your 
contribution in the best possible way, please go through the checklist below, 
which will get the contribution into a shape in which it can be best reviewed.*
   
   *Please understand that we do not do this to make contributions to Flink a 
hassle. In order to uphold a high standard of quality for code contributions, 
while at the same time managing a large number of contributions, we need 
contributors to prepare the contributions well, and give reviewers enough 
contextual information for the review. Please also understand that 
contributions that do not follow this guide will take longer to review and thus 
typically be picked up with lower priority by the community.*
   
   ## Contribution Checklist
   
     - Make sure that the pull request corresponds to a [JIRA 
issue](https://issues.apache.org/jira/projects/FLINK/issues). Exceptions are 
made for typos in JavaDoc or documentation files, which need no JIRA issue.
     
     - Name the pull request in the form "[FLINK-XXXX] [component] Title of the 
pull request", where *FLINK-XXXX* should be replaced by the actual issue 
number. Skip *component* if you are unsure about which is the best component.
     Typo fixes that have no associated JIRA issue should be named following 
this pattern: `[hotfix] [docs] Fix typo in event time introduction` or 
`[hotfix] [javadocs] Expand JavaDoc for PuncuatedWatermarkGenerator`.
   
     - Fill out the template below to describe the changes contributed by the 
pull request. That will give reviewers the context they need to do the review.
     
     - Make sure that the change passes the automated tests, i.e., `mvn clean 
verify` passes. You can set up Azure Pipelines CI to do that following [this 
guide](https://cwiki.apache.org/confluence/display/FLINK/Azure+Pipelines#AzurePipelines-Tutorial:SettingupAzurePipelinesforaforkoftheFlinkrepository).
   
     - Each pull request should address only one issue, not mix up code from 
multiple issues.
     
     - Each commit in the pull request has a meaningful commit message 
(including the JIRA id)
   
     - Once all items of the checklist are addressed, remove the above text and 
this checklist, leaving only the filled out template below.
   
   
   **(The sections below can be removed for hotfixes of typos)**
   -->
   
   ## What is the purpose of the change
   
   Currently, the SortMergeResultPartition selects to use HashBasedDataBuffer 
and SortBasedDataBuffer based on the number of required buffers per result 
partition decided by `taskmanager.network.sort-shuffle.min-buffers`. If the 
configured value is large enough, HashBasedDataBuffer will be used, otherwise, 
SortBasedDataBuffer will be used. Usually, the HashBasedDataBuffer has better 
performance. However, it is not easy to tune this value, because if a user 
tries to increase it for better performance, he/she is easy to encounter the 
'Insufficient number of network buffers' error. 
   
   This patch improves this case by selecting HashBasedDataBuffer and 
SortBasedDataBuffer dynamically based on the number of network buffers that can 
be allocated. More specifically, if there are enough buffers at runtime, 
HashBasedDataBuffer will be used, otherwise, SortBasedDataBuffer will be used. 
To achieve better performance, the user only needs to increase the total amount 
of network memory per task manager.
   
   
   ## Brief change log
   
     - *Select HashBasedDataBuffer and SortBasedDataBuffer dynamically based on 
the number of network buffers that can be allocated for 
SortMergeResultPartition*
   
   ## Verifying this change
   
   This change is already covered by existing tests, such as 
*SortMergeResultPartitionTest, DataBufferTest*.
   
   ## Does this pull request potentially affect one of the following parts:
   
     - Dependencies (does it add or upgrade a dependency): (yes / **no**)
     - The public API, i.e., is any changed class annotated with 
`@Public(Evolving)`: (yes / **no**)
     - The serializers: (yes / **no** / don't know)
     - The runtime per-record code paths (performance sensitive): (yes / **no** 
/ don't know)
     - Anything that affects deployment or recovery: JobManager (and its 
components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (yes / **no** / don't 
know)
     - The S3 file system connector: (yes / **no** / don't know)
   
   ## Documentation
   
     - Does this pull request introduce a new feature? (yes / **no**)
     - If yes, how is the feature documented? (**not applicable** / docs / 
JavaDocs / not documented)
   


-- 
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]

Reply via email to