There was actually a problem with the RateLimitedOutputStream implementation where the first second doesn't write anything because of integer rounding.
So RateLimitedOutputStream was overly aggressive in throttling.
Author: Reynold Xin <rxin@apache.org>
Closes#55 from rxin/ratelimitest and squashes the following commits:
52ce1b7 [Reynold Xin] SPARK-1158: Fix flaky RateLimitedOutputStreamSuite.
This lets us explicitly include Avro based on a profile for 0.23.X
builds. It makes me sad how convoluted it is to express this logic
in Maven. @tgraves and @sryza curious if this works for you.
I'm also considering just reverting to how it was before. The only
real problem was that Spark advertised a dependency on Avro
even though it only really depends transitively on Avro through
other deps.
Author: Patrick Wendell <pwendell@gmail.com>
Closes#49 from pwendell/avro-build-fix and squashes the following commits:
8d6ee92 [Patrick Wendell] SPARK-1121: Add avro to yarn-alpha profile
(Ported from https://github.com/apache/incubator-spark/pull/650 )
This adds one more change though, to fix the scala version warning introduced by json4s recently.
Author: Sean Owen <sowen@cloudera.com>
Closes#32 from srowen/SPARK-1084.2 and squashes the following commits:
9240abd [Sean Owen] Avoid scala version conflict in scalap induced by json4s dependency
1561cec [Sean Owen] Remove "exclude *" dependencies that are causing Maven warnings, and that are apparently unneeded anyway
This test has been flaky. We can re-enable it after @tdas has a chance to look at it.
Author: Reynold Xin <rxin@apache.org>
Closes#54 from rxin/ratelimit and squashes the following commits:
1a12198 [Reynold Xin] Ignore RateLimitedOutputStreamSuite for now.
This removes some loose ends not caught by the other (incubating -> tlp) patches. @markhamstra this updates the version as you mentioned earlier.
Author: Patrick Wendell <pwendell@gmail.com>
Closes#51 from pwendell/tlp and squashes the following commits:
d553b1b [Patrick Wendell] Remove remaining references to incubation
(Ported from https://github.com/apache/incubator-spark/pull/637 )
Author: Sean Owen <sowen@cloudera.com>
Closes#31 from srowen/SPARK-1084.1 and squashes the following commits:
6c4a32c [Sean Owen] Suppress warnings about legitimate unchecked array creations, or change code to avoid it
f35b833 [Sean Owen] Fix two misc javadoc problems
254e8ef [Sean Owen] Fix one new style error introduced in scaladoc warning commit
5b2fce2 [Sean Owen] Fix scaladoc invocation warning, and enable javac warnings properly, with plugin config updates
007762b [Sean Owen] Remove dead scaladoc links
b8ff8cb [Sean Owen] Replace deprecated Ant <tasks> with <target>
Prompted by a recent thread on the mailing list, I tried and failed to see if Spark can be made independent of log4j. There are a few cases where control of the underlying logging is pretty useful, and to do that, you have to bind to a specific logger.
Instead I propose some tidying that leaves Spark's use of log4j, but gets rid of warnings and should still enable downstream users to switch. The idea is to pipe everything (except log4j) through SLF4J, and have Spark use SLF4J directly when logging, and where Spark needs to output info (REPL and tests), bind from SLF4J to log4j.
This leaves the same behavior in Spark. It means that downstream users who want to use something except log4j should:
- Exclude dependencies on log4j, slf4j-log4j12 from Spark
- Include dependency on log4j-over-slf4j
- Include dependency on another logger X, and another slf4j-X
- Recreate any log config that Spark does, that is needed, in the other logger's config
That sounds about right.
Here are the key changes:
- Include the jcl-over-slf4j shim everywhere by depending on it in core.
- Exclude dependencies on commons-logging from third-party libraries.
- Include the jul-to-slf4j shim everywhere by depending on it in core.
- Exclude slf4j-* dependencies from third-party libraries to prevent collision or warnings
- Added missing slf4j-log4j12 binding to GraphX, Bagel module tests
And minor/incidental changes:
- Update to SLF4J 1.7.5, which happily matches Hadoop 2’s version and is a recommended update over 1.7.2
- (Remove a duplicate HBase dependency declaration in SparkBuild.scala)
- (Remove a duplicate mockito dependency declaration that was causing warnings and bugging me)
Author: Sean Owen <sowen@cloudera.com>
Closes#570 from srowen/SPARK-1071 and squashes the following commits:
52eac9f [Sean Owen] Add slf4j-over-log4j12 dependency to core (non-test) and remove it from things that depend on core.
77a7fa9 [Sean Owen] SPARK-1071: Tidy logging strategy and use of log4j
SPARK-1058, Fix Style Errors and Add Scala Style to Spark Build. Pt 2
Continuation of PR #557
With this all scala style errors are fixed across the code base !!
The reason for creating a separate PR was to not interrupt an already reviewed and ready to merge PR. Hope this gets reviewed soon and merged too.
Author: Prashant Sharma <prashant.s@imaginea.com>
Closes#567 and squashes the following commits:
3b1ec30 [Prashant Sharma] scala style fixes
Version number to 1.0.0-SNAPSHOT
Since 0.9.0-incubating is done and out the door, we shouldn't be building 0.9.0-incubating-SNAPSHOT anymore.
@pwendell
Author: Mark Hamstra <markhamstra@gmail.com>
== Merge branch commits ==
commit 1b00a8a7c1a7f251b4bb3774b84b9e64758eaa71
Author: Mark Hamstra <markhamstra@gmail.com>
Date: Wed Feb 5 09:30:32 2014 -0800
Version number to 1.0.0-SNAPSHOT
Change the ⇒ character (maybe from scalariform) to => in Scala code for style consistency
Looks like there are some ⇒ Unicode character (maybe from scalariform) in Scala code.
This PR is to change it to => to get some consistency on the Scala code.
If we want to use ⇒ as default we could use sbt plugin scalariform to make sure all Scala code has ⇒ instead of =>
And remove unused imports found in TwitterInputDStream.scala while I was there =)
Author: Henry Saputra <hsaputra@apache.org>
== Merge branch commits ==
commit 29c1771d346dff901b0b778f764e6b4409900234
Author: Henry Saputra <hsaputra@apache.org>
Date: Sat Feb 1 22:05:16 2014 -0800
Change the ⇒ character (maybe from scalariform) to => in Scala code for style consistency.
This fixes an issue where collectAsMap() could
fail when called on a JavaPairRDD that was derived
by transforming a non-JavaPairRDD.
The root problem was that we were creating the
JavaPairRDD's ClassTag by casting a
ClassTag[AnyRef] to a ClassTag[Tuple2[K2, V2]].
To fix this, I cast a ClassTag[Tuple2[_, _]]
instead, since this actually produces a ClassTag
of the appropriate type because ClassTags don't
capture type parameters:
scala> implicitly[ClassTag[Tuple2[_, _]]] == implicitly[ClassTag[Tuple2[Int, Int]]]
res8: Boolean = true
scala> implicitly[ClassTag[AnyRef]].asInstanceOf[ClassTag[Tuple2[Int, Int]]] == implicitly[ClassTag[Tuple2[Int, Int]]]
res9: Boolean = false
Automatically unpersisting RDDs that have been cleaned up from DStreams
Earlier RDDs generated by DStreams were forgotten but not unpersisted. The system relied on the natural BlockManager LRU to drop the data. The cleaner.ttl was a hammer to clean up RDDs but it is something that needs to be set separately and need to be set very conservatively (at best, few minutes). This automatic unpersisting allows the system to handle this automatically, which reduces memory usage. As a side effect it will also improve GC performance as there are less number of objects stored in memory. In fact, for some workloads, it may allow RDDs to be cached as deserialized, which speeds up processing without too much GC overheads.
This is disabled by default. To enable it set configuration spark.streaming.unpersist to true. In future release, this will be set to true by default.
Also, reduced sleep time in TaskSchedulerImpl.stop() from 5 second to 1 second. From my conversation with Matei, there does not seem to be any good reason for the sleep for letting messages be sent out be so long.
Improved logic of finding new files in FileInputDStream
Earlier, if HDFS has a hiccup and reports a existence of a new file (mod time T sec) at time T + 1 sec, then fileStream could have missed that file. With this change, it should be able to find files that are delayed by up to <batch size> seconds. That is, even if file is reported at T + <batch time> sec, file stream should be able to catch it.
The new logic, at a high level, is as follows. It keeps track of the new files it found in the previous interval and mod time of the oldest of those files (lets call it X). Then in the current interval, it will ignore those files that were seen in the previous interval and those which have mod time older than X. So if a new file gets reported by HDFS that in the current interval, but has mod time in the previous interval, it will be considered. However, if the mod time earlier than the previous interval (that is, earlier than X), they will be ignored. This is the current limitation, and future version would improve this behavior further.
Also reduced line lengths in DStream to <=100 chars.
Moved DStream and PairDSream to org.apache.spark.streaming.dstream
Similar to the package location of `org.apache.spark.rdd.RDD`, `DStream` has been moved from `org.apache.spark.streaming.DStream` to `org.apache.spark.streaming.dstream.DStream`. I know that the package name is a little long, but I think its better to keep it consistent with Spark's structure.
Also fixed persistence of windowed DStream. The RDDs generated generated by windowed DStream are essentially unions of underlying RDDs, and persistent these union RDDs would store numerous copies of the underlying data. Instead setting the persistence level on the windowed DStream is made to set the persistence level of the underlying DStream.
Remove now un-needed hostPort option
I noticed this was logging some scary error messages in various places. After I looked into it, this is no longer really used. I removed the option and re-wrote the one remaining use case (it was unnecessary there anyways).
Remove simple redundant return statements for Scala methods/functions
Remove simple redundant return statements for Scala methods/functions:
-) Only change simple return statements at the end of method
-) Ignore the complex if-else check
-) Ignore the ones inside synchronized
-) Add small changes to making var to val if possible and remove () for simple get
This hopefully makes the review simpler =)
Pass compile and tests.
Better error handling in Spark Streaming and more API cleanup
Earlier errors in jobs generated by Spark Streaming (or in the generation of jobs) could not be caught from the main driver thread (i.e. the thread that called StreamingContext.start()) as it would be thrown in different threads. With this change, after `ssc.start`, one can call `ssc.awaitTermination()` which will be block until the ssc is closed, or there is an exception. This makes it easier to debug.
This change also adds ssc.stop(<stop-spark-context>) where you can stop StreamingContext without stopping the SparkContext.
Also fixes the bug that came up with PRs #393 and #381. MetadataCleaner default value has been changed from 3500 to -1 for normal SparkContext and 3600 when creating a StreamingContext. Also, updated StreamingListenerBus with changes similar to SparkListenerBus in #392.
And changed a lot of protected[streaming] to private[streaming].
`foreachRDD` makes it clear that the granularity of this operator is per-RDD.
As it stands, `foreach` is inconsistent with with `map`, `filter`, and the other
DStream operators which get pushed down to individual records within each RDD.
API for automatic driver recovery for streaming programs and other bug fixes
1. Added Scala and Java API for automatically loading checkpoint if it exists in the provided checkpoint directory.
Scala API: `StreamingContext.getOrCreate(<checkpoint dir>, <function to create new StreamingContext>)` returns a StreamingContext
Java API: `JavaStreamingContext.getOrCreate(<checkpoint dir>, <factory obj of type JavaStreamingContextFactory>)`, return a JavaStreamingContext
See the RecoverableNetworkWordCount below as an example of how to use it.
2. Refactored streaming.Checkpoint*** code to fix bugs and make the DStream metadata checkpoint writing and reading more robust. Specifically, it fixes and improves the logic behind backing up and writing metadata checkpoint files. Also, it ensure that spark.driver.* and spark.hostPort is cleared from SparkConf before being written to checkpoint.
3. Fixed bug in cleaning up of checkpointed RDDs created by DStream. Specifically, this fix ensures that checkpointed RDD's files are not prematurely cleaned up, thus ensuring reliable recovery.
4. TimeStampedHashMap is upgraded to optionally update the timestamp on map.get(key). This allows clearing of data based on access time (i.e., clear records were last accessed before a threshold timestamp).
5. Added caching for file modification time in FileInputDStream using the updated TimeStampedHashMap. Without the caching, enumerating the mod times to find new files can take seconds if there are 1000s of files. This cache is automatically cleared.
This PR is not entirely final as I may make some minor additions - a Java examples, and adding StreamingContext.getOrCreate to unit test.
Edit: Java example to be added later, unit test added.
External Sorting for Aggregator and CoGroupedRDDs (Revisited)
(This pull request is re-opened from https://github.com/apache/incubator-spark/pull/303, which was closed because Jenkins / github was misbehaving)
The target issue for this patch is the out-of-memory exceptions triggered by aggregate operations such as reduce, groupBy, join, and cogroup. The existing AppendOnlyMap used by these operations resides purely in memory, and grows with the size of the input data until the amount of allocated memory is exceeded. Under large workloads, this problem is aggravated by the fact that OOM frequently occurs only after a very long (> 1 hour) map phase, in which case the entire job must be restarted.
The solution is to spill the contents of this map to disk once a certain memory threshold is exceeded. This functionality is provided by ExternalAppendOnlyMap, which additionally sorts this buffer before writing it out to disk, and later merges these buffers back in sorted order.
Under normal circumstances in which OOM is not triggered, ExternalAppendOnlyMap is simply a wrapper around AppendOnlyMap and incurs little overhead. Only when the memory usage is expected to exceed the given threshold does ExternalAppendOnlyMap spill to disk.
Set default logging to WARN for Spark streaming examples.
This programatically sets the log level to WARN by default for streaming
tests. If the user has already specified a log4j.properties file,
the user's file will take precedence over this default.
This programatically sets the log level to WARN by default for streaming
tests. If the user has already specified a log4j.properties file,
the user's file will take precedence over this default.
Improvements to DStream window ops and refactoring of Spark's CheckpointSuite
- Added a new RDD - PartitionerAwareUnionRDD. Using this RDD, one can take multiple RDDs partitioned by the same partitioner and unify them into a single RDD while preserving the partitioner. So m RDDs with p partitions each will be unified to a single RDD with p partitions and the same partitioner. The preferred location for each partition of the unified RDD will be the most common preferred location of the corresponding partitions of the parent RDDs. For example, location of partition 0 of the unified RDD will be where most of partition 0 of the parent RDDs are located.
- Improved the performance of DStream's reduceByKeyAndWindow and groupByKeyAndWindow. Both these operations work by doing per-batch reduceByKey/groupByKey and then using PartitionerAwareUnionRDD to union the RDDs across the window. This eliminates a shuffle related to the window operation, which can reduce batch processing time by 30-40% for simple workloads.
- Fixed bugs and simplified Spark's CheckpointSuite. Some of the tests were incorrect and unreliable. Added missing tests for ZippedRDD. I can go into greater detail if necessary.
- Added mapSideCombine option to combineByKeyAndWindow.
Also replaced SparkConf.getOrElse with just a "get" that takes a default
value, and added getInt, getLong, etc to make code that uses this
simpler later on.
- Got rid of global SparkContext.globalConf
- Pass SparkConf to serializers and compression codecs
- Made SparkConf public instead of private[spark]
- Improved API of SparkContext and SparkConf
- Switched executor environment vars to be passed through SparkConf
- Fixed some places that were still using system properties
- Fixed some tests, though others are still failing
This still fails several tests in core, repl and streaming, likely due
to properties not being set or cleared correctly (some of the tests run
fine in isolation).
- Refactored Scheduler + JobManager to JobGenerator + JobScheduler and
added JobSet for cleaner code. Moved scheduler related code to
streaming.scheduler package.
- Added StreamingListener trait (similar to SparkListener) to enable
gathering to streaming stats like processing times and delays.
StreamingContext.addListener() to added listeners.
- Deduped some code in streaming tests by modifying TestSuiteBase, and
added StreamingListenerSuite.
- Made file stream more robust to transient failures.
- Changed Spark.setCheckpointDir API to not have the second
'useExisting' parameter. Spark will always create a unique directory
for checkpointing underneath the directory provide to the funtion.
- Fixed bug wrt local relative paths as checkpoint directory.
- Made DStream and RDD checkpointing use
SparkContext.hadoopConfiguration, so that more HDFS compatible
filesystems are supported for checkpointing.
I've diff'd this patch against my own -- since they were both created
independently, this means that two sets of eyes have gone over all the
merge conflicts that were created, so I'm feeling significantly more
confident in the resulting PR.
@rxin has looked at the changes to the repl and is resoundingly
confident that they are correct.
Kafka uses an older version of jopt that causes bad conflicts with the version
used by spark-perf. It's not easy to remove this downstream because of the way
that spark-perf uses Spark (by including a spark assembly as an unmanaged jar).
This fixes the problem at its source by just never including it.
This patch adds an operator called repartition with more straightforward
semantics than the current `coalesce` operator. There are a few use cases
where this operator is useful:
1. If a user wants to increase the number of partitions in the RDD. This
is more common now with streaming. E.g. a user is ingesting data on one
node but they want to add more partitions to ensure parallelism of
subsequent operations across threads or the cluster.
Right now they have to call rdd.coalesce(numSplits, shuffle=true) - that's
super confusing.
2. If a user has input data where the number of partitions is not known. E.g.
> sc.textFile("some file").coalesce(50)....
This is both vague semantically (am I growing or shrinking this RDD) but also,
may not work correctly if the base RDD has fewer than 50 partitions.
The new operator forces shuffles every time, so it will always produce exactly
the number of new partitions. It also throws an exception rather than silently
not-working if a bad input is passed.
I am currently adding streaming tests (requires refactoring some of the test
suite to allow testing at partition granularity), so this is not ready for
merge yet. But feedback is welcome.
MQTT Adapter for Spark Streaming
MQTT is a machine-to-machine (M2M)/Internet of Things connectivity protocol.
It was designed as an extremely lightweight publish/subscribe messaging transport. You may read more about it here http://mqtt.org/
Message Queue Telemetry Transport (MQTT) is an open message protocol for M2M communications. It enables the transfer of telemetry-style data in the form of messages from devices like sensors and actuators, to mobile phones, embedded systems on vehicles, or laptops and full scale computers.
The protocol was invented by Andy Stanford-Clark of IBM, and Arlen Nipper of Cirrus Link Solutions
This protocol enables a publish/subscribe messaging model in an extremely lightweight way. It is useful for connections with remote locations where line of code and network bandwidth is a constraint.
MQTT is one of the widely used protocol for 'Internet of Things'. This protocol is getting much attraction as anything and everything is getting connected to internet and they all produce data. Researchers and companies predict some 25 billion devices will be connected to the internet by 2015.
Plugin/Support for MQTT is available in popular MQs like RabbitMQ, ActiveMQ etc.
Support for MQTT in Spark will help people with Internet of Things (IoT) projects to use Spark Streaming for their real time data processing needs (from sensors and other embedded devices etc).
Serialize and restore spark.cleaner.ttl to savepoint
In accordance to conversation in spark-dev maillist, preserve spark.cleaner.ttl parameter when serializing checkpoint.
This is an unfortunately invasive change which converts all of our BlockId
strings into actual BlockId types. Here are some advantages of doing this now:
+ Type safety
+ Code clarity - it's now obvious what the key of a shuffle or rdd block is,
for instance. Additionally, appearing in tuple/map type signatures is a big
readability bonus. A Seq[(String, BlockStatus)] is not very clear.
Further, we can now use more Scala features, like matching on BlockId types.
+ Explicit usage - we can now formally tell where various BlockIds are being used
(without doing string searches); this makes updating current BlockIds a much
clearer process, and compiler-supported.
(I'm looking at you, shuffle file consolidation.)
+ It will only get harder to make this change as time goes on.
Since this touches a lot of files, it'd be best to either get this patch
in quickly or throw it on the ground to avoid too many secondary merge conflicts.
Conflicts:
bagel/pom.xml
core/pom.xml
core/src/test/scala/org/apache/spark/ui/UISuite.scala
examples/pom.xml
mllib/pom.xml
pom.xml
project/SparkBuild.scala
repl/pom.xml
streaming/pom.xml
tools/pom.xml
In scala 2.10, a shorter representation is used for naming artifacts
so changed to shorter scala version for artifacts and made it a property in pom.
variable conditional on if its set, and created addCredentials in each of the SparkHadoopUtil classes
to only add the credentials when the profile is hadoop2-yarn.
Shuffle Performance Optimization: do not send 0-byte block requests to reduce network messages
change reference from io.Source to scala.io.Source to avoid looking into io.netty package
Signed-off-by: shane-huang <shengsheng.huang@intel.com>