commit | 3ce67acb0494a47c167f938323917c0bbca32b7d | [log] [tgz] |
---|---|---|
author | Bharath Kumarasubramanian <bharathkk@apache.org> | Fri Aug 04 14:44:10 2023 -0700 |
committer | GitHub <noreply@github.com> | Fri Aug 04 14:44:10 2023 -0700 |
tree | d7b14c030290f09453b8f6722ea345708ccc8761 | |
parent | 9357a9101c7000296a3fb1cac576e4988db92169 [diff] |
SAMZA-2789: Remove cap on intermediate stream partition count for stream mode (#1679) Problem: Intermediate stream partition count inference logic caps the partition size to 256 resulting in imbalances in work assignments to tasks Description: As part of the intermediate partition size inference logic, we currently employ the following algorithm. partitionCount = Math.max(maxPartitionSize(inputStreams), maxPartitionSize(outputStreams)) cap the partitionCount to MAX_INFERRED_PARTITIONS defined in the IntermediateStreamManager which is 256 apply the inferred partition count to intermediate streams whose partition count is uninitialized The logic above always caps the partition size of intermediate streams to 256 for all auto-created intermediate streams. This can prevent the job from scaling up uniformly as the intermediate partition assignment is capped to 256 tasks thereby rendering other tasks imbalanced in case of number tasks > 256. Changes: Apply the cap only for batch mode as 256 limit was introduced for batch mode where number of files (partition) could be large Add unit tests for IntermediateStreamManager Minor java doc fix for DefaultTaskExecutorFactory Tests: Added unit tests for the code changes API Changes: None Upgrade Instructions: Jobs that are temporarily worked around this constraint by setting job.intermediate.stream.partitions should remove the configuration in order for samza to infer and apply the partition count as described above Jobs that don't use job.intermediate.stream.partitions need no changes. Usage Instructions: Refer to upgrade instruction.
Apache Samza is a distributed stream processing framework. It uses Apache Kafka for messaging, and Apache Hadoop YARN to provide fault tolerance, processor isolation, security, and resource management.
Samza's key features include:
Check out Hello Samza to try Samza. Read the Background page to learn more about Samza.
To build Samza from a git checkout, run:
./gradlew clean build
To build Samza from a source release, it is first necessary to download the gradle wrapper script above. This bootstrapping process requires Gradle to be installed on the source machine. Gradle is available through most package managers or directly from its website. To bootstrap the wrapper, run:
gradle -b bootstrap.gradle
After the bootstrap script has completed, the regular gradlew instructions below are available.
This project is built with Java 8 and can run in a Java 8 runtime enviornment. Additionally, it also supports running in a Java 11 runtime environment. If you intend to use Samza in a Java 11 runtime environment, it means you will also need to use YARN 3.3.4+ and in which case, you should also use the samza-yarn3
module (built with YARN 3.3.4) instead of the samza-yarn
(built with YARN 2.10.1). There is also a samza-shell-yarn3
that depends on the samza-yarn3
module, so use that shell module if you intend on using Yarn 3.
Samza builds with Scala 2.11 or 2.12 and YARN 2.10.1, by default. Use the -PscalaSuffix switches to change Scala versions. Samza supports building Scala with 2.11 and 2.12 and provides a YARN 2 module (samze-yarn
) and a YARN 3 module (samza-yarn3
).
NOTE: Some modules currently do not officially support Java 11 Runtime and are still using the YARN 2.10.1 dependency:
samza-yarn
samza-shell
samza-test
samza-hdfs
./gradlew -PscalaSuffix=2.12 clean build
Also, you can make use of bin/check-all.sh
in order to test multiple variants of Java JDKs, Scala, and Yarn.
To run all tests:
./gradlew clean test
To run a single test:
./gradlew clean :samza-test:test -Dtest.single=TestStatefulTask
To run key-value performance tests:
./gradlew samza-shell:kvPerformanceTest -PconfigPath=file://$PWD/samza-test/src/main/config/perf/kv-perf.properties
To run yarn integration tests:
./bin/integration-tests.sh <dir> yarn-integration-tests
To run standalone integration tests:
./bin/integration-tests.sh <dir> standalone-integration-tests
./gradlew checkstyleMain checkstyleTest
To run a job (defined in a properties file):
./gradlew samza-shell:runJob -PconfigPath=/path/to/job/config.properties
To inspect a job's latest checkpoint:
./gradlew samza-shell:checkpointTool -PconfigPath=/path/to/job/config.properties
To modify a job's checkpoint (assumes that the job is not currently running), give it a file with the new offset for each partition, in the format systems.<system>.streams.<topic>.partitions.<partition>=<offset>
:
./gradlew samza-shell:checkpointTool -PconfigPath=/path/to/job/config.properties \ -PnewOffsets=file:///path/to/new/offsets.properties
To get Eclipse projects, run:
./gradlew eclipse
For IntelliJ, run:
./gradlew idea
To start contributing on Samza please read Rules and Contributor Corner. Notice that Samza git repository does not support git pull request.
Apache Samza is a top level project of the Apache Software Foundation.