GitHub user pnowojski opened a pull request:
https://github.com/apache/flink/pull/5105
[FLINK-8178][network] Introduce not threadsafe write only BufferBuilder
This pr depends on #5104
While Buffer class is used in multithreaded context it requires
synchronisation. Previously it was miss-leading and unclear, suggesting that
RecordSerializer should take into account synchronisation of the Buffer that's
holding. With NotThreadSafe BufferBuilder there is now clear separation between
single-threaded writing/creating a BufferBuilder and multithreaded Buffer
handling/retaining/recycling.
## Verifying this change
*(Please pick either of the following options)*
This change is already covered by existing tests in `flink-runtime`.
## 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, Yarn/Mesos, 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)
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/pnowojski/flink f8178
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/flink/pull/5105.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #5105
----
commit d807b9246a2f68e0ea8991047954396adc4703c2
Author: Piotr Nowojski <[email protected]>
Date: 2017-11-28T15:49:37Z
[FLINK-8172][network] Write to memorySegment directly in RecordSerializer
This increases throughput of network stack by factor of 2, because
previously
method getMemorySegment() was called twice per record and it is a
synchronized
method on recycleLock, while RecordSerializer is sole owner of the Buffer at
this point, so synchronisation is not needed.
commit e88506d15885b0d7e60fdc9f930725e83e959fbb
Author: Piotr Nowojski <[email protected]>
Date: 2017-11-29T15:33:06Z
[hotfix][network] Drop redundant this reference usages
commit 245363a0b6e0f9a93405f71be50ad00d4083c9c5
Author: Piotr Nowojski <[email protected]>
Date: 2017-11-29T16:58:56Z
[FLINK-8178][network] Introduce not threadsafe write only BufferBuilder
While Buffer class is used in multithreaded context it requires
synchronisation.
Previously it was miss-leading and unclear, suggesting that
RecordSerializer should
take into account synchronisation of the Buffer that's holding. With
NotThreadSafe
BufferBuilder there is now clear separation between single-threaded
writing/creating
a BufferBuilder and multithreaded Buffer handling/retaining/recycling.
----
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