> On Sept. 13, 2016, 12:33 a.m., Yi Pan (Data Infrastructure) wrote: > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/HdfsSystemConsumer.java, > > line 101 > > <https://reviews.apache.org/r/51142/diff/5/?file=1493801#file1493801line101> > > > > Better, to avoid the wasteful remote IO if there are multiple calls to > > getPartitionDescriptor from multiple threads, is to use bucketized locks on > > the ConcurrentHashMap entries to ensure synchronization in populating a > > certain hash map entry. Guava cache implemented the bucketized locking as a > > built-in method already: > > http://www.tutorialspoint.com/guava/guava_caching_utilities.htm > > Navina Ramesh wrote: > What was the resolution here? Was there any change to the IO pattern to > use caching? > > Hai Lu wrote: > I believe this is just to optimize the situation that multiple calls > happen at the same time and causing everyone making remote calls. After the > change here, only the first one will actually make the remote call while > everyone else be blocked. > > It's a very very tiny improvement, to be honest.
Ah.Got it.. Actually I was looking for the change in the diff window and I couldn't figure out where you have used. I understood once I applied your patch in my IDE. Thanks! Yes . It is tiny but important improvement. - Navina ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/51142/#review148612 ----------------------------------------------------------- On Sept. 20, 2016, 11:22 p.m., Hai Lu wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/51142/ > ----------------------------------------------------------- > > (Updated Sept. 20, 2016, 11:22 p.m.) > > > Review request for samza, Chris Pettitt, Yi Pan (Data Infrastructure), and > Navina Ramesh. > > > Bugs: SAMZA-967 > https://issues.apache.org/jira/browse/SAMZA-967 > > > Repository: samza > > > Description > ------- > > Add HDFS System Consumer: > > 1. System admin, partitioner > 2. System consumer with metrics > > Design doc can be found here: > https://issues.apache.org/jira/secure/attachment/12824078/HDFSSystemConsumer.pdf > > An overview of the high level architecture: > > The system factory is used by Samza to instantiate SystemConsumer, > SystemProducer, and SystemAdmin for a specific system. The > FileDataSystemFactory can be reused for other file system like sources. > > HDFSSystemAdmin will start a “DirectoryPartitioner” to figure out the set of > HDFS files need to be consumed for this job. The DirectoryPartitioner also > uses “GroupingPattern” to group files into partitions if advanced > partitioning is required. HDFSSystemAdmin will then persist the > “PartitionDescriptor” to HDFS. > > The HDFSSystemConsumer will then pick up the “PartitionDescriptor” from HDFS. > Based on this information as well as the actual assignment of partitions, it > would then know which files to read from. > > The initial implementation of the HDFS system consumer supports only avro > data files. It’s very easy to extend it to a variety of file format by > implementing the FileReader interface. > > > > > +------------------------------------------------------------------------------+ > > | > | > +-----------------+ HDFS > | > | Obtain | > | > | Partition > +------+----------------------^------+---------------------------------^-------+ > > | Description | | | > | > | | | | > | > | +-------------v-------+ | | > Filtering/ | > | | | | +---+ > Grouping +-----+ > | | HDFSAvroFileReader | | | > | > | | | Persist | | > | > | +---------+-----------+ Partition | | > | > | | Description | > +------v--------------+ +----------+----------+ > | | | | > | | | > | +---------+-----------+ | |Directory > Partitioner| | HDFSAvroWriter | > | | IFileReader | | | > | | | > | | | | > +------+--------------+ +----------+----------+ > | +---------+-----------+ | | > | > | | | | > | > | | | | > | > | +---------+-----------+ > +-+----------+--------+ +----------+----------+ > | | | | > | | | > | | HDFSSystemConsumer | | HDFSSystemAdmin > | | HDFSSystemProducer | > +----------> | | > | | | > +---------+-----------+ > +-----------+---------+ +----------+----------+ > | | > | > > +------------------------------------+------------------------------------+ > > | > > > +---------------------------------------+--------------------------------------+ > > | > | > | HDFSSystemFactory > | > | > | > > +------------------------------------------------------------------------------+ > > > Diffs > ----- > > build.gradle 1d4eb74b1294318db8454631ddd0901596121ab2 > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/HdfsSystemAdmin.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/HdfsSystemConsumer.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/PartitionDescriptorUtil.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/partitioner/DirectoryPartitioner.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/partitioner/FileSystemAdapter.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/partitioner/HdfsFileSystemAdapter.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/reader/AvroFileHdfsReader.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/reader/HdfsReaderFactory.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/reader/MultiFileHdfsReader.java > PRE-CREATION > > samza-hdfs/src/main/java/org/apache/samza/system/hdfs/reader/SingleFileHdfsReader.java > PRE-CREATION > samza-hdfs/src/main/scala/org/apache/samza/system/hdfs/HdfsConfig.scala > 61b7570afae3219b618c8830905035063941bdd7 > > samza-hdfs/src/main/scala/org/apache/samza/system/hdfs/HdfsSystemAdmin.scala > 92eb4472533db67dca01f075cb460581b4bdac0d > > samza-hdfs/src/main/scala/org/apache/samza/system/hdfs/HdfsSystemFactory.scala > ef3c20a097ddf2feecaf8b0ad4587ea4bf6570b7 > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/TestHdfsSystemConsumer.java > PRE-CREATION > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/TestPartitionDesctiptorUtil.java > PRE-CREATION > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/partitioner/TestDirectoryPartitioner.java > PRE-CREATION > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/partitioner/TestHdfsFileSystemAdapter.java > PRE-CREATION > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/reader/TestAvroFileHdfsReader.java > PRE-CREATION > > samza-hdfs/src/test/java/org/apache/samza/system/hdfs/reader/TestMultiFileHdfsReader.java > PRE-CREATION > samza-hdfs/src/test/resources/integTest/emptyTestFile PRE-CREATION > samza-hdfs/src/test/resources/partitioner/testfile01 PRE-CREATION > samza-hdfs/src/test/resources/partitioner/testfile02 PRE-CREATION > samza-hdfs/src/test/resources/reader/TestEvent.avsc PRE-CREATION > > samza-hdfs/src/test/scala/org/apache/samza/system/hdfs/TestHdfsSystemProducerTestSuite.scala > 261310d03de204718621f601117f016da14841df > samza-shell/src/main/bash/bash-run-job.sh PRE-CREATION > samza-yarn/src/main/java/org/apache/samza/job/yarn/YarnContainerRunner.java > dacc52de0a34498a715a299bc69c95aebd1b08ba > samza-yarn/src/main/scala/org/apache/samza/job/yarn/YarnJobFactory.scala > 4e328a5f8c2b496a71e36c106339b7af263c96c7 > > Diff: https://reviews.apache.org/r/51142/diff/ > > > Testing > ------- > > unit tests pass. > > manually tested by writing a real hdfs samza job and deploying to a yarn > cluster. > > > Thanks, > > Hai Lu > >
