micheal-o opened a new pull request, #48685:
URL: https://github.com/apache/spark/pull/48685
<!--
Thanks for sending a pull request! Here are some tips for you:
1. If this is your first time, please read our contributor guidelines:
https://spark.apache.org/contributing.html
2. Ensure you have added or run the appropriate tests for your PR:
https://spark.apache.org/developer-tools.html
3. If the PR is unfinished, add '[WIP]' in your PR title, e.g.,
'[WIP][SPARK-XXXX] Your PR title ...'.
4. Be sure to keep the PR description updated to reflect all changes.
5. Please write your PR title to summarize what this PR proposes.
6. If possible, provide a concise example to reproduce the issue for a
faster review.
7. If you want to add a new configuration, please read the guideline first
for naming configurations in
'core/src/main/scala/org/apache/spark/internal/config/ConfigEntry.scala'.
8. If you want to add or modify an error type or message, please read the
guideline first in
'common/utils/src/main/resources/error/README.md'.
-->
### What changes were proposed in this pull request?
There are 2 bugs in the recently added new approach for RocksDB SST file
mapping in this PR: https://github.com/apache/spark/pull/47875 (cc @sahnib )
1. The file mapping version is not properly advancing and only advances when
we are reopening the RocksDB. This causes ineffective file reuse and we end up
not reusing files that should have been reused. Leading to a lot of unnecessary
file upload/download, and in the worst case it will make us act like file reuse
is disabled.
2. Ineffective file reuse when creating a checkpoint. We currently will not
reuse the files for creating checkpoint, if it was added in the current version
i.e. if you do load(v1) -> save(v2), the SST files loaded in v1 will not be
reused in v2, and we will upload them again.
3. These two bugs were not caught even though we have tests to catch them,
because there was also a bug in the test.
NOTE: these bugs will not cause corruption and more of a performance bug.
They just make file reuse ineffective. And end up working like there's no file
reuse enabled. i.e. A lot of file upload/download
**To Repro**:
You can add the test changes in this PR to current master and run RocksDB
test, you will see test failures for file mapping version not advancing and for
incorrect file reuse.
### Why are the changes needed?
Bug fix. Without this change, it will work like file reuse is disabled. This
is a performance bug.
### Does this PR introduce _any_ user-facing change?
<!--
Note that it means *any* user-facing change including all aspects such as
the documentation fix.
If yes, please clarify the previous behavior and the change this PR proposes
- provide the console output, description and/or an example to show the
behavior difference if possible.
If possible, please also clarify if this is a user-facing change compared to
the released Spark versions or within the unreleased branches such as master.
If no, write 'No'.
-->
No
### How was this patch tested?
<!--
If tests were added, say they were added here. Please make sure to add some
test cases that check the changes thoroughly including negative and positive
cases if possible.
If it was tested in a way different from regular unit tests, please clarify
how you tested step by step, ideally copy and paste-able, so that other
reviewers can test and check, and descendants can verify in the future.
If tests were not added, please describe why they were not added and/or why
it was difficult to add.
If benchmark tests were added, please run the benchmarks in GitHub Actions
for the consistent environment, and the instructions could accord to:
https://spark.apache.org/developer-tools.html#github-workflow-benchmarks.
-->
Existing tests fixed and added assertion
### Was this patch authored or co-authored using generative AI tooling?
<!--
If generative AI tooling has been used in the process of authoring this
patch, please include the
phrase: 'Generated-by: ' followed by the name of the tool and its version.
If no, write 'No'.
Please refer to the [ASF Generative Tooling
Guidance](https://www.apache.org/legal/generative-tooling.html) for details.
-->
No
--
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]
