yzang2019 opened a new pull request, #22754:
URL: https://github.com/apache/flink/pull/22754
<!--
*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
Problem:
Currently, if we have hundreds or thousands of history jobs sitting in HDFS,
everytime when we restart or redeploy history server, it will take 30 minutes
or up to hours to show some data on the web page. During this time, the history
server is loading all the history job metadata from HDFS to build local
webviews, however the web page is not usable since there's no content showing
up until all jobs are done for the first round.
Goal:
This PR is aiming to
- Improve the time and speed of displaying history completed jobs on startup
- Improve the performance of history server processing a single job by
adding parallelism
- Improve the overall user experience of history server
## Brief change log
- Add a new configuration for history server to set the number of workers
for parallelizm
- Optimized the logic for history server webview update:
Before: Update the webview only after we finish processing ALL job achieves
After: Update the webview each time we finish processing a new job archive
## Verifying this change
- Added corresponding unit test for verify the new configuration.
- Modified existing unit test to cover multi-threaded scenario.
- Manually did integration test and canary in Twitter's environment with
hundreds of job history
--
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]
