Commit graph

47 commits

Author SHA1 Message Date
jerryshao e1960c3d6f [SPARK-22062][CORE] Spill large block to disk in BlockManager's remote fetch to avoid OOM
## What changes were proposed in this pull request?

In the current BlockManager's `getRemoteBytes`, it will call `BlockTransferService#fetchBlockSync` to get remote block. In the `fetchBlockSync`, Spark will allocate a temporary `ByteBuffer` to store the whole fetched block. This will potentially lead to OOM if block size is too big or several blocks are fetched simultaneously in this executor.

So here leveraging the idea of shuffle fetch, to spill the large block to local disk before consumed by upstream code. The behavior is controlled by newly added configuration, if block size is smaller than the threshold, then this block will be persisted in memory; otherwise it will first spill to disk, and then read from disk file.

To achieve this feature, what I did is:

1. Rename `TempShuffleFileManager` to `TempFileManager`, since now it is not only used by shuffle.
2. Add a new `TempFileManager` to manage the files of fetched remote blocks, the files are tracked by weak reference, will be deleted when no use at all.

## How was this patch tested?

This was tested by adding UT, also manual verification in local test to perform GC to clean the files.

Author: jerryshao <sshao@hortonworks.com>

Closes #19476 from jerryshao/SPARK-22062.
2017-10-17 22:54:38 +08:00
Thomas Graves a74ec6d7bb [SPARK-22218] spark shuffle services fails to update secret on app re-attempts
This patch fixes application re-attempts when running spark on yarn using the external shuffle service with security on.  Currently executors will fail to launch on any application re-attempt when launched on a nodemanager that had an executor from the first attempt.  The reason for this is because we aren't updating the secret key after the first application attempt.  The fix here is to just remove the containskey check to see if it already exists. In this way, we always add it and make sure its the most recent secret.  Similarly remove the check for containsKey on the remove since its just adding extra check that isn't really needed.

Note this worked before spark 2.2 because the check used to be contains (which was looking for the value) rather then containsKey, so that never matched and it was just always adding the new secret.

Patch was tested on a 10 node cluster as well as added the unit test.
The test ran was a wordcount where the output directory already existed.  With the bug present the application attempt failed with max number of executor Failures which were all saslExceptions.  With the fix present the application re-attempts fail with directory already exists or when you remove the directory between attempts the re-attemps succeed.

Author: Thomas Graves <tgraves@unharmedunarmed.corp.ne1.yahoo.com>

Closes #19450 from tgravescs/SPARK-22218.
2017-10-09 12:56:37 -07:00
jerryshao 1da5822e6a [SPARK-21934][CORE] Expose Shuffle Netty memory usage to MetricsSystem
## What changes were proposed in this pull request?

This is a followup work of SPARK-9104 to expose the Netty memory usage to MetricsSystem. Current the shuffle Netty memory usage of `NettyBlockTransferService` will be exposed, if using external shuffle, then the Netty memory usage of `ExternalShuffleClient` and `ExternalShuffleService` will be exposed instead. Currently I don't expose Netty memory usage of `YarnShuffleService`, because `YarnShuffleService` doesn't have `MetricsSystem` itself, and is better to connect to Hadoop's MetricsSystem.

## How was this patch tested?

Manually verified in local cluster.

Author: jerryshao <sshao@hortonworks.com>

Closes #19160 from jerryshao/SPARK-21934.
2017-09-21 13:54:30 +08:00
Sanket Chintapalli 1662e93119 [SPARK-21501] Change CacheLoader to limit entries based on memory footprint
Right now the spark shuffle service has a cache for index files. It is based on a # of files cached (spark.shuffle.service.index.cache.entries). This can cause issues if people have a lot of reducers because the size of each entry can fluctuate based on the # of reducers.
We saw an issues with a job that had 170000 reducers and it caused NM with spark shuffle service to use 700-800MB or memory in NM by itself.
We should change this cache to be memory based and only allow a certain memory size used. When I say memory based I mean the cache should have a limit of say 100MB.

https://issues.apache.org/jira/browse/SPARK-21501

Manual Testing with 170000 reducers has been performed with cache loaded up to max 100MB default limit, with each shuffle index file of size 1.3MB. Eviction takes place as soon as the total cache size reaches the 100MB limit and the objects will be ready for garbage collection there by avoiding NM to crash. No notable difference in runtime has been observed.

Author: Sanket Chintapalli <schintap@yahoo-inc.com>

Closes #18940 from redsanket/SPARK-21501.
2017-08-23 11:51:11 -05:00
jerryshao 5fd0294ff8 [SPARK-21475][CORE] Use NIO's Files API to replace FileInputStream/FileOutputStream in some critical paths
## What changes were proposed in this pull request?

Java's `FileInputStream` and `FileOutputStream` overrides finalize(), even this file input/output stream is closed correctly and promptly, it will still leave some memory footprints which will only get cleaned in Full GC. This will introduce two side effects:

1. Lots of memory footprints regarding to Finalizer will be kept in memory and this will increase the memory overhead. In our use case of external shuffle service, a busy shuffle service will have bunch of this object and potentially lead to OOM.
2. The Finalizer will only be called in Full GC, and this will increase the overhead of Full GC and lead to long GC pause.

https://bugs.openjdk.java.net/browse/JDK-8080225

https://www.cloudbees.com/blog/fileinputstream-fileoutputstream-considered-harmful

So to fix this potential issue, here propose to use NIO's Files#newInput/OutputStream instead in some critical paths like shuffle.

Left unchanged FileInputStream in core which I think is not so critical:

```
./core/src/main/scala/org/apache/spark/api/python/PythonRDD.scala:467:    val file = new DataInputStream(new FileInputStream(filename))
./core/src/main/scala/org/apache/spark/api/python/PythonRDD.scala:942:    val in = new FileInputStream(new File(path))
./core/src/main/scala/org/apache/spark/deploy/master/FileSystemPersistenceEngine.scala:76:    val fileIn = new FileInputStream(file)
./core/src/main/scala/org/apache/spark/deploy/RPackageUtils.scala:248:        val fis = new FileInputStream(file)
./core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala:910:                input = new FileInputStream(new File(t))
./core/src/main/scala/org/apache/spark/metrics/MetricsConfig.scala:20:import java.io.{FileInputStream, InputStream}
./core/src/main/scala/org/apache/spark/metrics/MetricsConfig.scala:132:        case Some(f) => new FileInputStream(f)
./core/src/main/scala/org/apache/spark/scheduler/SchedulableBuilder.scala:20:import java.io.{FileInputStream, InputStream}
./core/src/main/scala/org/apache/spark/scheduler/SchedulableBuilder.scala:77:        val fis = new FileInputStream(f)
./core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala:27:import org.apache.spark.io.NioBufferedFileInputStream
./core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala:94:      new DataInputStream(new NioBufferedFileInputStream(index))
./core/src/main/scala/org/apache/spark/storage/DiskStore.scala:111:        val channel = new FileInputStream(file).getChannel()
./core/src/main/scala/org/apache/spark/storage/DiskStore.scala:219:    val channel = new FileInputStream(file).getChannel()
./core/src/main/scala/org/apache/spark/TestUtils.scala:20:import java.io.{ByteArrayInputStream, File, FileInputStream, FileOutputStream}
./core/src/main/scala/org/apache/spark/TestUtils.scala:106:      val in = new FileInputStream(file)
./core/src/main/scala/org/apache/spark/util/logging/RollingFileAppender.scala:89:        inputStream = new FileInputStream(activeFile)
./core/src/main/scala/org/apache/spark/util/Utils.scala:329:      if (in.isInstanceOf[FileInputStream] && out.isInstanceOf[FileOutputStream]
./core/src/main/scala/org/apache/spark/util/Utils.scala:332:        val inChannel = in.asInstanceOf[FileInputStream].getChannel()
./core/src/main/scala/org/apache/spark/util/Utils.scala:1533:      gzInputStream = new GZIPInputStream(new FileInputStream(file))
./core/src/main/scala/org/apache/spark/util/Utils.scala:1560:      new GZIPInputStream(new FileInputStream(file))
./core/src/main/scala/org/apache/spark/util/Utils.scala:1562:      new FileInputStream(file)
./core/src/main/scala/org/apache/spark/util/Utils.scala:2090:    val inReader = new InputStreamReader(new FileInputStream(file), StandardCharsets.UTF_8)
```

Left unchanged FileOutputStream in core:

```
./core/src/main/scala/org/apache/spark/api/python/PythonRDD.scala:957:    val out = new FileOutputStream(file)
./core/src/main/scala/org/apache/spark/api/r/RBackend.scala:20:import java.io.{DataOutputStream, File, FileOutputStream, IOException}
./core/src/main/scala/org/apache/spark/api/r/RBackend.scala:131:      val dos = new DataOutputStream(new FileOutputStream(f))
./core/src/main/scala/org/apache/spark/deploy/master/FileSystemPersistenceEngine.scala:62:    val fileOut = new FileOutputStream(file)
./core/src/main/scala/org/apache/spark/deploy/RPackageUtils.scala:160:          val outStream = new FileOutputStream(outPath)
./core/src/main/scala/org/apache/spark/deploy/RPackageUtils.scala:239:    val zipOutputStream = new ZipOutputStream(new FileOutputStream(zipFile, false))
./core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala:949:        val out = new FileOutputStream(tempFile)
./core/src/main/scala/org/apache/spark/deploy/worker/CommandUtils.scala:20:import java.io.{File, FileOutputStream, InputStream, IOException}
./core/src/main/scala/org/apache/spark/deploy/worker/CommandUtils.scala:106:    val out = new FileOutputStream(file, true)
./core/src/main/scala/org/apache/spark/scheduler/EventLoggingListener.scala:109:     * Therefore, for local files, use FileOutputStream instead. */
./core/src/main/scala/org/apache/spark/scheduler/EventLoggingListener.scala:112:        new FileOutputStream(uri.getPath)
./core/src/main/scala/org/apache/spark/storage/DiskBlockObjectWriter.scala:20:import java.io.{BufferedOutputStream, File, FileOutputStream, OutputStream}
./core/src/main/scala/org/apache/spark/storage/DiskBlockObjectWriter.scala:71:  private var fos: FileOutputStream = null
./core/src/main/scala/org/apache/spark/storage/DiskBlockObjectWriter.scala:102:    fos = new FileOutputStream(file, true)
./core/src/main/scala/org/apache/spark/storage/DiskBlockObjectWriter.scala:213:      var truncateStream: FileOutputStream = null
./core/src/main/scala/org/apache/spark/storage/DiskBlockObjectWriter.scala:215:        truncateStream = new FileOutputStream(file, true)
./core/src/main/scala/org/apache/spark/storage/DiskStore.scala:153:    val out = new FileOutputStream(file).getChannel()
./core/src/main/scala/org/apache/spark/TestUtils.scala:20:import java.io.{ByteArrayInputStream, File, FileInputStream, FileOutputStream}
./core/src/main/scala/org/apache/spark/TestUtils.scala:81:    val jarStream = new JarOutputStream(new FileOutputStream(jarFile))
./core/src/main/scala/org/apache/spark/TestUtils.scala:96:    val jarFileStream = new FileOutputStream(jarFile)
./core/src/main/scala/org/apache/spark/util/logging/FileAppender.scala:20:import java.io.{File, FileOutputStream, InputStream, IOException}
./core/src/main/scala/org/apache/spark/util/logging/FileAppender.scala:31:  volatile private var outputStream: FileOutputStream = null
./core/src/main/scala/org/apache/spark/util/logging/FileAppender.scala:97:    outputStream = new FileOutputStream(file, true)
./core/src/main/scala/org/apache/spark/util/logging/RollingFileAppender.scala:90:        gzOutputStream = new GZIPOutputStream(new FileOutputStream(gzFile))
./core/src/main/scala/org/apache/spark/util/Utils.scala:329:      if (in.isInstanceOf[FileInputStream] && out.isInstanceOf[FileOutputStream]
./core/src/main/scala/org/apache/spark/util/Utils.scala:333:        val outChannel = out.asInstanceOf[FileOutputStream].getChannel()
./core/src/main/scala/org/apache/spark/util/Utils.scala:527:      val out = new FileOutputStream(tempFile)
```

Here in `DiskBlockObjectWriter`, it uses `FileDescriptor` so it is not easy to change to NIO Files API.

For the `FileInputStream` and `FileOutputStream` in common/shuffle* I changed them all.

## How was this patch tested?

Existing tests and manual verification.

Author: jerryshao <sshao@hortonworks.com>

Closes #18684 from jerryshao/SPARK-21475.
2017-08-01 10:23:45 +01:00
Marcelo Vanzin 300807c6e3 [SPARK-21494][NETWORK] Use correct app id when authenticating to external service.
There was some code based on the old SASL handler in the new auth client that
was incorrectly using the SASL user as the user to authenticate against the
external shuffle service. This caused the external service to not be able to
find the correct secret to authenticate the connection, failing the connection.

In the course of debugging, I found that some log messages from the YARN shuffle
service were a little noisy, so I silenced some of them, and also added a couple
of new ones that helped find this issue. On top of that, I found that a check
in the code that records app secrets was wrong, causing more log spam and also
using an O(n) operation instead of an O(1) call.

Also added a new integration suite for the YARN shuffle service with auth on,
and verified it failed before, and passes now.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #18706 from vanzin/SPARK-21494.
2017-07-25 17:57:26 -07:00
Shixiong Zhu 833eab2c9b [SPARK-21369][CORE] Don't use Scala Tuple2 in common/network-*
## What changes were proposed in this pull request?

Remove all usages of Scala Tuple2 from common/network-* projects. Otherwise, Yarn users cannot use `spark.reducer.maxReqSizeShuffleToMem`.

## How was this patch tested?

Jenkins.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #18593 from zsxwing/SPARK-21369.
2017-07-11 11:26:17 +08:00
jinxing 6a06c4b03c [SPARK-21342] Fix DownloadCallback to work well with RetryingBlockFetcher.
## What changes were proposed in this pull request?

When `RetryingBlockFetcher` retries fetching blocks. There could be two `DownloadCallback`s download the same content to the same target file. It could cause `ShuffleBlockFetcherIterator` reading a partial result.

This pr proposes to create and delete the tmp files in `OneForOneBlockFetcher`

Author: jinxing <jinxing6042@126.com>
Author: Shixiong Zhu <zsxwing@gmail.com>

Closes #18565 from jinxing64/SPARK-21342.
2017-07-10 21:06:58 +08:00
Li Yichao d107b3b910 [SPARK-20640][CORE] Make rpc timeout and retry for shuffle registration configurable.
## What changes were proposed in this pull request?

Currently the shuffle service registration timeout and retry has been hardcoded. This works well for small workloads but under heavy workload when the shuffle service is busy transferring large amount of data we see significant delay in responding to the registration request, as a result we often see the executors fail to register with the shuffle service, eventually failing the job. We need to make these two parameters configurable.

## How was this patch tested?

* Updated `BlockManagerSuite` to test registration timeout and max attempts configuration actually works.

cc sitalkedia

Author: Li Yichao <lyc@zhihu.com>

Closes #18092 from liyichao/SPARK-20640.
2017-06-21 21:54:29 +08:00
Dongjoon Hyun ecc5631351 [MINOR][BUILD] Fix Java linter errors
## What changes were proposed in this pull request?

This PR cleans up a few Java linter errors for Apache Spark 2.2 release.

## How was this patch tested?

```bash
$ dev/lint-java
Using `mvn` from path: /usr/local/bin/mvn
Checkstyle checks passed.
```

We can check the result at Travis CI, [here](https://travis-ci.org/dongjoon-hyun/spark/builds/244297894).

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #18345 from dongjoon-hyun/fix_lint_java_2.
2017-06-19 20:17:54 +01:00
jinxing 93dd0c518d [SPARK-20994] Remove redundant characters in OpenBlocks to save memory for shuffle service.
## What changes were proposed in this pull request?

In current code, blockIds in `OpenBlocks` are stored in the iterator on shuffle service.
There are some redundant characters in  blockId(`"shuffle_" + shuffleId + "_" + mapId + "_" + reduceId`). This pr proposes to improve the footprint and alleviate the memory pressure on shuffle service.

Author: jinxing <jinxing6042@126.com>

Closes #18231 from jinxing64/SPARK-20994-v2.
2017-06-16 20:09:45 +08:00
jinxing 3f94e64aa8 [SPARK-19659] Fetch big blocks to disk when shuffle-read.
## What changes were proposed in this pull request?

Currently the whole block is fetched into memory(off heap by default) when shuffle-read. A block is defined by (shuffleId, mapId, reduceId). Thus it can be large when skew situations. If OOM happens during shuffle read, job will be killed and users will be notified to "Consider boosting spark.yarn.executor.memoryOverhead". Adjusting parameter and allocating more memory can resolve the OOM. However the approach is not perfectly suitable for production environment, especially for data warehouse.
Using Spark SQL as data engine in warehouse, users hope to have a unified parameter(e.g. memory) but less resource wasted(resource is allocated but not used). The hope is strong especially when migrating data engine to Spark from another one(e.g. Hive). Tuning the parameter for thousands of SQLs one by one is very time consuming.
It's not always easy to predict skew situations, when happen, it make sense to fetch remote blocks to disk for shuffle-read, rather than kill the job because of OOM.

In this pr, I propose to fetch big blocks to disk(which is also mentioned in SPARK-3019):

1. Track average size and also the outliers(which are larger than 2*avgSize) in MapStatus;
2. Request memory from `MemoryManager` before fetch blocks and release the memory to `MemoryManager` when `ManagedBuffer` is released.
3. Fetch remote blocks to disk when failing acquiring memory from `MemoryManager`, otherwise fetch to memory.

This is an improvement for memory control when shuffle blocks and help to avoid OOM in scenarios like below:
1. Single huge block;
2. Sizes of many blocks are underestimated in `MapStatus` and the actual footprint of blocks is much larger than the estimated.

## How was this patch tested?
Added unit test in `MapStatusSuite` and `ShuffleBlockFetcherIteratorSuite`.

Author: jinxing <jinxing6042@126.com>

Closes #16989 from jinxing64/SPARK-19659.
2017-05-25 16:11:30 +08:00
jinxing 85c6ce6193 [SPARK-20426] Lazy initialization of FileSegmentManagedBuffer for shuffle service.
## What changes were proposed in this pull request?
When application contains large amount of shuffle blocks. NodeManager requires lots of memory to keep metadata(`FileSegmentManagedBuffer`) in `StreamManager`. When the number of shuffle blocks is big enough. NodeManager can run OOM. This pr proposes to do lazy initialization of `FileSegmentManagedBuffer` in shuffle service.

## How was this patch tested?

Manually test.

Author: jinxing <jinxing6042@126.com>

Closes #17744 from jinxing64/SPARK-20426.
2017-04-27 14:06:07 -05:00
Josh Rosen f44c8a843c [SPARK-20453] Bump master branch version to 2.3.0-SNAPSHOT
This patch bumps the master branch version to `2.3.0-SNAPSHOT`.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #17753 from JoshRosen/SPARK-20453.
2017-04-24 21:48:04 -07:00
Sean Owen 1487c9af20
[SPARK-19534][TESTS] Convert Java tests to use lambdas, Java 8 features
## What changes were proposed in this pull request?

Convert tests to use Java 8 lambdas, and modest related fixes to surrounding code.

## How was this patch tested?

Jenkins tests

Author: Sean Owen <sowen@cloudera.com>

Closes #16964 from srowen/SPARK-19534.
2017-02-19 09:42:50 -08:00
Sean Owen 0e2405490f
[SPARK-19550][BUILD][CORE][WIP] Remove Java 7 support
- Move external/java8-tests tests into core, streaming, sql and remove
- Remove MaxPermGen and related options
- Fix some reflection / TODOs around Java 8+ methods
- Update doc references to 1.7/1.8 differences
- Remove Java 7/8 related build profiles
- Update some plugins for better Java 8 compatibility
- Fix a few Java-related warnings

For the future:

- Update Java 8 examples to fully use Java 8
- Update Java tests to use lambdas for simplicity
- Update Java internal implementations to use lambdas

## How was this patch tested?

Existing tests

Author: Sean Owen <sowen@cloudera.com>

Closes #16871 from srowen/SPARK-19493.
2017-02-16 12:32:45 +00:00
Josh Rosen 1c4d10b10c [SPARK-19529] TransportClientFactory.createClient() shouldn't call awaitUninterruptibly()
## What changes were proposed in this pull request?

This patch replaces a single `awaitUninterruptibly()` call with a plain `await()` call in Spark's `network-common` library in order to fix a bug which may cause tasks to be uncancellable.

In Spark's Netty RPC layer, `TransportClientFactory.createClient()` calls `awaitUninterruptibly()` on a Netty future while waiting for a connection to be established. This creates problem when a Spark task is interrupted while blocking in this call (which can happen in the event of a slow connection which will eventually time out). This has bad impacts on task cancellation when `interruptOnCancel = true`.

As an example of the impact of this problem, I experienced significant numbers of uncancellable "zombie tasks" on a production cluster where several tasks were blocked trying to connect to a dead shuffle server and then continued running as zombies after I cancelled the associated Spark stage. The zombie tasks ran for several minutes with the following stack:

```
java.lang.Object.wait(Native Method)
java.lang.Object.wait(Object.java:460)
io.netty.util.concurrent.DefaultPromise.await0(DefaultPromise.java:607)
io.netty.util.concurrent.DefaultPromise.awaitUninterruptibly(DefaultPromise.java:301)
org.apache.spark.network.client.TransportClientFactory.createClient(TransportClientFactory.java:224)
org.apache.spark.network.client.TransportClientFactory.createClient(TransportClientFactory.java:179) => holding Monitor(java.lang.Object1849476028})
org.apache.spark.network.shuffle.ExternalShuffleClient$1.createAndStart(ExternalShuffleClient.java:105)
org.apache.spark.network.shuffle.RetryingBlockFetcher.fetchAllOutstanding(RetryingBlockFetcher.java:140)
org.apache.spark.network.shuffle.RetryingBlockFetcher.start(RetryingBlockFetcher.java:120)
org.apache.spark.network.shuffle.ExternalShuffleClient.fetchBlocks(ExternalShuffleClient.java:114)
org.apache.spark.storage.ShuffleBlockFetcherIterator.sendRequest(ShuffleBlockFetcherIterator.scala:169)
org.apache.spark.storage.ShuffleBlockFetcherIterator.fetchUpToMaxBytes(ShuffleBlockFetcherIterator.scala:
350)
org.apache.spark.storage.ShuffleBlockFetcherIterator.initialize(ShuffleBlockFetcherIterator.scala:286)
org.apache.spark.storage.ShuffleBlockFetcherIterator.<init>(ShuffleBlockFetcherIterator.scala:120)
org.apache.spark.shuffle.BlockStoreShuffleReader.read(BlockStoreShuffleReader.scala:45)
org.apache.spark.sql.execution.ShuffledRowRDD.compute(ShuffledRowRDD.scala:169)
org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:323)
org.apache.spark.rdd.RDD.iterator(RDD.scala:287)
[...]
```

As far as I can tell, `awaitUninterruptibly()` might have been used in order to avoid having to declare that methods throw `InterruptedException` (this code is written in Java, hence the need to use checked exceptions). This patch simply replaces this with a regular, interruptible `await()` call,.

This required several interface changes to declare a new checked exception (these are internal interfaces, though, and this change doesn't significantly impact binary compatibility).

An alternative approach would be to wrap `InterruptedException` into `IOException` in order to avoid having to change interfaces. The problem with this approach is that the `network-shuffle` project's `RetryingBlockFetcher` code treats `IOExceptions` as transitive failures when deciding whether to retry fetches, so throwing a wrapped `IOException` might cause an interrupted shuffle fetch to be retried, further prolonging the lifetime of a cancelled zombie task.

Note that there are three other `awaitUninterruptibly()` in the codebase, but those calls have a hard 10 second timeout and are waiting on a `close()` operation which is expected to complete near instantaneously, so the impact of uninterruptibility there is much smaller.

## How was this patch tested?

Manually.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #16866 from JoshRosen/SPARK-19529.
2017-02-13 11:04:27 -08:00
Marcelo Vanzin 8f3f73abc1 [SPARK-19139][CORE] New auth mechanism for transport library.
This change introduces a new auth mechanism to the transport library,
to be used when users enable strong encryption. This auth mechanism
has better security than the currently used DIGEST-MD5.

The new protocol uses symmetric key encryption to mutually authenticate
the endpoints, and is very loosely based on ISO/IEC 9798.

The new protocol falls back to SASL when it thinks the remote end is old.
Because SASL does not support asking the server for multiple auth protocols,
which would mean we could re-use the existing SASL code by just adding a
new SASL provider, the protocol is implemented outside of the SASL API
to avoid the boilerplate of adding a new provider.

Details of the auth protocol are discussed in the included README.md
file.

This change partly undos the changes added in SPARK-13331; AES encryption
is now decoupled from SASL authentication. The encryption code itself,
though, has been re-used as part of this change.

## How was this patch tested?

- Unit tests
- Tested Spark 2.2 against Spark 1.6 shuffle service with SASL enabled
- Tested Spark 2.2 against Spark 2.2 shuffle service with SASL fallback disabled

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #16521 from vanzin/SPARK-19139.
2017-01-24 10:44:04 -08:00
Ryan Williams afd9bc1d8a [SPARK-17807][CORE] split test-tags into test-JAR
Remove spark-tag's compile-scope dependency (and, indirectly, spark-core's compile-scope transitive-dependency) on scalatest by splitting test-oriented tags into spark-tags' test JAR.

Alternative to #16303.

Author: Ryan Williams <ryan.blake.williams@gmail.com>

Closes #16311 from ryan-williams/tt.
2016-12-21 16:37:20 -08:00
Marcelo Vanzin bc59951bab [SPARK-18773][CORE] Make commons-crypto config translation consistent.
This change moves the logic that translates Spark configuration to
commons-crypto configuration to the network-common module. It also
extends TransportConf and ConfigProvider to provide the necessary
interfaces for the translation to work.

As part of the change, I removed SystemPropertyConfigProvider, which
was mostly used as an "empty config" in unit tests, and adjusted the
very few tests that required a specific config.

I also changed the config keys for AES encryption to live under the
"spark.network." namespace, which is more correct than their previous
names under "spark.authenticate.".

Tested via existing unit test.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #16200 from vanzin/SPARK-18773.
2016-12-12 16:27:04 -08:00
Reynold Xin c7c7265950 [SPARK-18695] Bump master branch version to 2.2.0-SNAPSHOT
## What changes were proposed in this pull request?
This patch bumps master branch version to 2.2.0-SNAPSHOT.

## How was this patch tested?
N/A

Author: Reynold Xin <rxin@databricks.com>

Closes #16126 from rxin/SPARK-18695.
2016-12-02 21:09:37 -08:00
Jagadeesan b2e2726244 [SPARK-17543] Missing log4j config file for tests in common/network-…
## What changes were proposed in this pull request?

The Maven module `common/network-shuffle` does not have a log4j configuration file for its test cases. So, added `log4j.properties` in the directory `src/test/resources`.

…shuffle]

Author: Jagadeesan <as2@us.ibm.com>

Closes #15108 from jagadeesanas2/SPARK-17543.
2016-09-16 10:18:45 +01:00
Thomas Graves e79962f2f3 [SPARK-16711] YarnShuffleService doesn't re-init properly on YARN rolling upgrade
The Spark Yarn Shuffle Service doesn't re-initialize the application credentials early enough which causes any other spark executors trying to fetch from that node during a rolling upgrade to fail with "java.lang.NullPointerException: Password cannot be null if SASL is enabled".  Right now the spark shuffle service relies on the Yarn nodemanager to re-register the applications, unfortunately this is after we open the port for other executors to connect. If other executors connected before the re-register they get a null pointer exception which isn't a re-tryable exception and cause them to fail pretty quickly. To solve this I added another leveldb file so that it can save and re-initialize all the applications before opening the port for other executors to connect to it.  Adding another leveldb was simpler from the code structure point of view.

Most of the code changes are moving things to common util class.

Patch was tested manually on a Yarn cluster with rolling upgrade was happing while spark job was running. Without the patch I consistently get the NullPointerException, with the patch the job gets a few Connection refused exceptions but the retries kick in and the it succeeds.

Author: Thomas Graves <tgraves@staydecay.corp.gq1.yahoo.com>

Closes #14718 from tgravescs/SPARK-16711.
2016-09-02 10:42:13 -07:00
Sean Owen 5d84c7fd83 [SPARK-17332][CORE] Make Java Loggers static members
## What changes were proposed in this pull request?

Make all Java Loggers static members

## How was this patch tested?

Jenkins

Author: Sean Owen <sowen@cloudera.com>

Closes #14896 from srowen/SPARK-17332.
2016-08-31 11:09:14 -07:00
Michael Allman f209310719 [SPARK-17231][CORE] Avoid building debug or trace log messages unless the respective log level is enabled
(This PR addresses https://issues.apache.org/jira/browse/SPARK-17231)

## What changes were proposed in this pull request?

While debugging the performance of a large GraphX connected components computation, we found several places in the `network-common` and `network-shuffle` code bases where trace or debug log messages are constructed even if the respective log level is disabled. According to YourKit, these constructions were creating substantial churn in the eden region. Refactoring the respective code to avoid these unnecessary constructions except where necessary led to a modest but measurable reduction in our job's task time, GC time and the ratio thereof.

## How was this patch tested?

We computed the connected components of a graph with about 2.6 billion vertices and 1.7 billion edges four times. We used four different EC2 clusters each with 8 r3.8xl worker nodes. Two test runs used Spark master. Two used Spark master + this PR. The results from the first test run, master and master+PR:
![master](https://cloud.githubusercontent.com/assets/833693/17951634/7471cbca-6a18-11e6-9c26-78afe9319685.jpg)
![logging_perf_improvements](https://cloud.githubusercontent.com/assets/833693/17951632/7467844e-6a18-11e6-9a0e-053dc7650413.jpg)

The results from the second test run, master and master+PR:
![master 2](https://cloud.githubusercontent.com/assets/833693/17951633/746dd6aa-6a18-11e6-8e27-606680b3f105.jpg)
![logging_perf_improvements 2](https://cloud.githubusercontent.com/assets/833693/17951631/74488710-6a18-11e6-8a32-08692f373386.jpg)

Though modest, I believe these results are significant.

Author: Michael Allman <michael@videoamp.com>

Closes #14798 from mallman/spark-17231-logging_perf_improvements.
2016-08-25 11:57:38 -07:00
Josh Rosen d91c6755ae [HOTFIX] Remove unnecessary imports from #12944 that broke build
Author: Josh Rosen <joshrosen@databricks.com>

Closes #14499 from JoshRosen/hotfix.
2016-08-04 15:26:27 -07:00
Sital Kedia 9c15d079df [SPARK-15074][SHUFFLE] Cache shuffle index file to speedup shuffle fetch
## What changes were proposed in this pull request?

Shuffle fetch on large intermediate dataset is slow because the shuffle service open/close the index file for each shuffle fetch. This change introduces a cache for the index information so that we can avoid accessing the index files for each block fetch

## How was this patch tested?

Tested by running a job on the cluster and the shuffle read time was reduced by 50%.

Author: Sital Kedia <skedia@fb.com>

Closes #12944 from sitalkedia/shuffle_service.
2016-08-04 14:54:38 -07:00
Xin Ren 21a6dd2aef [SPARK-16535][BUILD] In pom.xml, remove groupId which is redundant definition and inherited from the parent
https://issues.apache.org/jira/browse/SPARK-16535

## What changes were proposed in this pull request?

When I scan through the pom.xml of sub projects, I found this warning as below and attached screenshot
```
Definition of groupId is redundant, because it's inherited from the parent
```
![screen shot 2016-07-13 at 3 13 11 pm](https://cloud.githubusercontent.com/assets/3925641/16823121/744f893e-4916-11e6-8a52-042f83b9db4e.png)

I've tried to remove some of the lines with groupId definition, and the build on my local machine is still ok.
```
<groupId>org.apache.spark</groupId>
```
As I just find now `<maven.version>3.3.9</maven.version>` is being used in Spark 2.x, and Maven-3 supports versionless parent elements: Maven 3 will remove the need to specify the parent version in sub modules. THIS is great (in Maven 3.1).

ref: http://stackoverflow.com/questions/3157240/maven-3-worth-it/3166762#3166762

## How was this patch tested?

I've tested by re-building the project, and build succeeded.

Author: Xin Ren <iamshrek@126.com>

Closes #14189 from keypointt/SPARK-16535.
2016-07-19 11:59:46 +01:00
Dongjoon Hyun 556a9437ac [MINOR][BUILD] Fix Java Linter LineLength errors
## What changes were proposed in this pull request?

This PR fixes four java linter `LineLength` errors. Those are all `LineLength` errors, but we had better remove all java linter errors before release.

## How was this patch tested?

After pass the Jenkins, `./dev/lint-java`.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #14255 from dongjoon-hyun/minor_java_linter.
2016-07-19 11:51:43 +01:00
Yangyang Liu 68df47aca5 [SPARK-16405] Add metrics and source for external shuffle service
## What changes were proposed in this pull request?

Since externalShuffleService is essential for spark, better monitoring for shuffle service is necessary. In order to do so, we added various metrics in shuffle service and imported into ExternalShuffleServiceSource for metric system.
Metrics added in shuffle service:
* registeredExecutorsSize
* openBlockRequestLatencyMillis
* registerExecutorRequestLatencyMillis
* blockTransferRateBytes

JIRA Issue: https://issues.apache.org/jira/browse/SPARK-16405

## How was this patch tested?

Some test cases are added to verify metrics as expected in metric system. Those unit test cases are shown in `ExternalShuffleBlockHandlerSuite `

Author: Yangyang Liu <yangyangliu@fb.com>

Closes #14080 from lovexi/yangyang-metrics.
2016-07-12 10:13:58 -07:00
Reynold Xin ffcb6e055a [SPARK-16477] Bump master version to 2.1.0-SNAPSHOT
## What changes were proposed in this pull request?
After SPARK-16476 (committed earlier today as #14128), we can finally bump the version number.

## How was this patch tested?
N/A

Author: Reynold Xin <rxin@databricks.com>

Closes #14130 from rxin/SPARK-16477.
2016-07-11 09:42:56 -07:00
Tejas Patil c1fd9cacba [SPARK-15263][CORE] Make shuffle service dir cleanup faster by using rm -rf
## What changes were proposed in this pull request?

Jira: https://issues.apache.org/jira/browse/SPARK-15263

The current logic for directory cleanup is slow because it does directory listing, recurses over child directories, checks for symbolic links, deletes leaf files and finally deletes the dirs when they are empty. There is back-and-forth switching from kernel space to user space while doing this. Since most of the deployment backends would be Unix systems, we could essentially just do `rm -rf` so that entire deletion logic runs in kernel space.

The current Java based impl in Spark seems to be similar to what standard libraries like guava and commons IO do (eg. http://svn.apache.org/viewvc/commons/proper/io/trunk/src/main/java/org/apache/commons/io/FileUtils.java?view=markup#l1540). However, guava removed this method in favour of shelling out to an operating system command (like in this PR). See the `Deprecated` note in older javadocs for guava for details : http://google.github.io/guava/releases/10.0.1/api/docs/com/google/common/io/Files.html#deleteRecursively(java.io.File)

Ideally, Java should be providing such APIs so that users won't have to do such things to get platform specific code. Also, its not just about speed, but also handling race conditions while doing at FS deletions is tricky. I could find this bug for Java in similar context : http://bugs.java.com/bugdatabase/view_bug.do?bug_id=7148952

## How was this patch tested?

I am relying on existing test cases to test the method. If there are suggestions about testing it, welcome to hear about it.

## Performance gains

*Input setup* : Created a nested directory structure of depth 3 and each entry having 50 sub-dirs. The input being cleaned up had total ~125k dirs.

Ran both approaches (in isolation) for 6 times to get average numbers:

Native Java cleanup  | `rm -rf` as a separate process
------------ | -------------
10.04 sec | 4.11 sec

This change made deletion 2.4 times faster for the given test input.

Author: Tejas Patil <tejasp@fb.com>

Closes #13042 from tejasapatil/delete_recursive.
2016-05-18 12:10:32 +01:00
Sean Owen 122302cbf5 [SPARK-15290][BUILD] Move annotations, like @Since / @DeveloperApi, into spark-tags
## What changes were proposed in this pull request?

(See https://github.com/apache/spark/pull/12416 where most of this was already reviewed and committed; this is just the module structure and move part. This change does not move the annotations into test scope, which was the apparently problem last time.)

Rename `spark-test-tags` -> `spark-tags`; move common annotations like `Since` to `spark-tags`

## How was this patch tested?

Jenkins tests.

Author: Sean Owen <sowen@cloudera.com>

Closes #13074 from srowen/SPARK-15290.
2016-05-17 09:55:53 +01:00
Dongjoon Hyun 2c170dd3d7 [SPARK-15134][EXAMPLE] Indent SparkSession builder patterns and update binary_classification_metrics_example.py
## What changes were proposed in this pull request?

This issue addresses the comments in SPARK-15031 and also fix java-linter errors.
- Use multiline format in SparkSession builder patterns.
- Update `binary_classification_metrics_example.py` to use `SparkSession`.
- Fix Java Linter errors (in SPARK-13745, SPARK-15031, and so far)

## How was this patch tested?

After passing the Jenkins tests and run `dev/lint-java` manually.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #12911 from dongjoon-hyun/SPARK-15134.
2016-05-05 14:37:50 -07:00
Thomas Graves 0c00391f77 [SPARK-15121] Improve logging of external shuffle handler
## What changes were proposed in this pull request?

Add more informative logging in the external shuffle service to aid in debugging who is connecting to the YARN Nodemanager when the external shuffle service runs under it.

## How was this patch tested?

Ran and saw logs coming out in log file.

Author: Thomas Graves <tgraves@staydecay.corp.gq1.yahoo.com>

Closes #12900 from tgravescs/SPARK-15121.
2016-05-04 14:28:26 -07:00
Yin Huai 9c7c42bc6a Revert "[SPARK-14613][ML] Add @Since into the matrix and vector classes in spark-mllib-local"
This reverts commit dae538a4d7.
2016-04-28 19:57:41 -07:00
Pravin Gadakh dae538a4d7 [SPARK-14613][ML] Add @Since into the matrix and vector classes in spark-mllib-local
## What changes were proposed in this pull request?

This PR adds `since` tag into the matrix and vector classes in spark-mllib-local.

## How was this patch tested?

Scala-style checks passed.

Author: Pravin Gadakh <prgadakh@in.ibm.com>

Closes #12416 from pravingadakh/SPARK-14613.
2016-04-28 15:59:18 -07:00
Lianhui Wang 6bfe42a3be [SPARK-14731][shuffle]Revert SPARK-12130 to make 2.0 shuffle service compatible with 1.x
## What changes were proposed in this pull request?
SPARK-12130 make 2.0 shuffle service incompatible with 1.x. So from discussion: [http://apache-spark-developers-list.1001551.n3.nabble.com/YARN-Shuffle-service-and-its-compatibility-td17222.html](url) we should maintain compatibility between Spark 1.x and Spark 2.x's shuffle service.
I put string comparison into executor's register at first avoid string comparison in getBlockData every time.

## How was this patch tested?
N/A

Author: Lianhui Wang <lianhuiwang09@gmail.com>

Closes #12568 from lianhuiwang/SPARK-14731.
2016-04-25 12:33:32 -07:00
Reynold Xin 5e92583d38 [SPARK-14667] Remove HashShuffleManager
## What changes were proposed in this pull request?
The sort shuffle manager has been the default since Spark 1.2. It is time to remove the old hash shuffle manager.

## How was this patch tested?
Removed some tests related to the old manager.

Author: Reynold Xin <rxin@databricks.com>

Closes #12423 from rxin/SPARK-14667.
2016-04-18 19:30:00 -07:00
Dongjoon Hyun 3f749f7ed4 [SPARK-14355][BUILD] Fix typos in Exception/Testcase/Comments and static analysis results
## What changes were proposed in this pull request?

This PR contains the following 5 types of maintenance fix over 59 files (+94 lines, -93 lines).
- Fix typos(exception/log strings, testcase name, comments) in 44 lines.
- Fix lint-java errors (MaxLineLength) in 6 lines. (New codes after SPARK-14011)
- Use diamond operators in 40 lines. (New codes after SPARK-13702)
- Fix redundant semicolon in 5 lines.
- Rename class `InferSchemaSuite` to `CSVInferSchemaSuite` in CSVInferSchemaSuite.scala.

## How was this patch tested?

Manual and pass the Jenkins tests.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #12139 from dongjoon-hyun/SPARK-14355.
2016-04-03 18:14:16 -07:00
Dongjoon Hyun 20fd254101 [SPARK-14011][CORE][SQL] Enable LineLength Java checkstyle rule
## What changes were proposed in this pull request?

[Spark Coding Style Guide](https://cwiki.apache.org/confluence/display/SPARK/Spark+Code+Style+Guide) has 100-character limit on lines, but it's disabled for Java since 11/09/15. This PR enables **LineLength** checkstyle again. To help that, this also introduces **RedundantImport** and **RedundantModifier**, too. The following is the diff on `checkstyle.xml`.

```xml
-        <!-- TODO: 11/09/15 disabled - the lengths are currently > 100 in many places -->
-        <!--
         <module name="LineLength">
             <property name="max" value="100"/>
             <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
         </module>
-        -->
         <module name="NoLineWrap"/>
         <module name="EmptyBlock">
             <property name="option" value="TEXT"/>
 -167,5 +164,7
         </module>
         <module name="CommentsIndentation"/>
         <module name="UnusedImports"/>
+        <module name="RedundantImport"/>
+        <module name="RedundantModifier"/>
```

## How was this patch tested?

Currently, `lint-java` is disabled in Jenkins. It needs a manual test.
After passing the Jenkins tests, `dev/lint-java` should passes locally.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #11831 from dongjoon-hyun/SPARK-14011.
2016-03-21 07:58:57 +00:00
Sean Owen 3b461d9ecd [SPARK-13823][SPARK-13397][SPARK-13395][CORE] More warnings, StandardCharset follow up
## What changes were proposed in this pull request?

Follow up to https://github.com/apache/spark/pull/11657

- Also update `String.getBytes("UTF-8")` to use `StandardCharsets.UTF_8`
- And fix one last new Coverity warning that turned up (use of unguarded `wait()` replaced by simpler/more robust `java.util.concurrent` classes in tests)
- And while we're here cleaning up Coverity warnings, just fix about 15 more build warnings

## How was this patch tested?

Jenkins tests

Author: Sean Owen <sowen@cloudera.com>

Closes #11725 from srowen/SPARK-13823.2.
2016-03-16 09:36:34 +00:00
Bertrand Bossy 310981d49a [SPARK-12583][MESOS] Mesos shuffle service: Don't delete shuffle files before application has stopped
## Problem description:

Mesos shuffle service is completely unusable since Spark 1.6.0 . The problem seems to occur since the move from akka to netty in the networking layer. Until now, a connection from the driver to each shuffle service was used as a signal for the shuffle service to determine, whether the driver is still running. Since 1.6.0, this connection is closed after spark.shuffle.io.connectionTimeout (or spark.network.timeout if the former is not set) due to it being idle. The shuffle service interprets this as a signal that the driver has stopped, despite the driver still being alive. Thus, shuffle files are deleted before the application has stopped.

### Context and analysis:

spark shuffle fails with mesos after 2mins: https://issues.apache.org/jira/browse/SPARK-12583
External shuffle service broken w/ Mesos: https://issues.apache.org/jira/browse/SPARK-13159

This is a follow up on #11207 .

## What changes were proposed in this pull request?

This PR adds a heartbeat signal from the Driver (in MesosExternalShuffleClient) to all registered external mesos shuffle service instances. In MesosExternalShuffleBlockHandler, a thread periodically checks whether a driver has timed out and cleans an application's shuffle files if this is the case.

## How was the this patch tested?

This patch has been tested on a small mesos test cluster using the spark-shell. Log output from mesos shuffle service:
```
16/02/19 15:13:45 INFO mesos.MesosExternalShuffleBlockHandler: Received registration request from app 294def07-3249-4e0f-8d71-bf8c83c58a50-0018 (remote address /xxx.xxx.xxx.xxx:52391, heartbeat timeout 120000 ms).
16/02/19 15:13:47 INFO shuffle.ExternalShuffleBlockResolver: Registered executor AppExecId{appId=294def07-3249-4e0f-8d71-bf8c83c58a50-0018, execId=3} with ExecutorShuffleInfo{localDirs=[/foo/blockmgr-c84c0697-a3f9-4f61-9c64-4d3ee227c047], subDirsPerLocalDir=64, shuffleManager=sort}
16/02/19 15:13:47 INFO shuffle.ExternalShuffleBlockResolver: Registered executor AppExecId{appId=294def07-3249-4e0f-8d71-bf8c83c58a50-0018, execId=7} with ExecutorShuffleInfo{localDirs=[/foo/blockmgr-bf46497a-de80-47b9-88f9-563123b59e03], subDirsPerLocalDir=64, shuffleManager=sort}
16/02/19 15:16:02 INFO mesos.MesosExternalShuffleBlockHandler: Application 294def07-3249-4e0f-8d71-bf8c83c58a50-0018 timed out. Removing shuffle files.
16/02/19 15:16:02 INFO shuffle.ExternalShuffleBlockResolver: Application 294def07-3249-4e0f-8d71-bf8c83c58a50-0018 removed, cleanupLocalDirs = true
16/02/19 15:16:02 INFO shuffle.ExternalShuffleBlockResolver: Cleaning up executor AppExecId{appId=294def07-3249-4e0f-8d71-bf8c83c58a50-0018, execId=3}'s 1 local dirs
16/02/19 15:16:02 INFO shuffle.ExternalShuffleBlockResolver: Cleaning up executor AppExecId{appId=294def07-3249-4e0f-8d71-bf8c83c58a50-0018, execId=7}'s 1 local dirs
```
Note: there are 2 executors running on this slave.

Author: Bertrand Bossy <bertrand.bossy@teralytics.net>

Closes #11272 from bbossy/SPARK-12583-mesos-shuffle-service-heartbeat.
2016-03-14 12:22:57 -07:00
Sean Owen 1840852841 [SPARK-13823][CORE][STREAMING][SQL] Always specify Charset in String <-> byte[] conversions (and remaining Coverity items)
## What changes were proposed in this pull request?

- Fixes calls to `new String(byte[])` or `String.getBytes()` that rely on platform default encoding, to use UTF-8
- Same for `InputStreamReader` and `OutputStreamWriter` constructors
- Standardizes on UTF-8 everywhere
- Standardizes specifying the encoding with `StandardCharsets.UTF-8`, not the Guava constant or "UTF-8" (which means handling `UnuspportedEncodingException`)
- (also addresses the other remaining Coverity scan issues, which are pretty trivial; these are separated into commit 1deecd8d9c )

## How was this patch tested?

Jenkins tests

Author: Sean Owen <sowen@cloudera.com>

Closes #11657 from srowen/SPARK-13823.
2016-03-13 21:03:49 -07:00
Dongjoon Hyun b5f02d6743 [SPARK-13583][CORE][STREAMING] Remove unused imports and add checkstyle rule
## What changes were proposed in this pull request?

After SPARK-6990, `dev/lint-java` keeps Java code healthy and helps PR review by saving much time.
This issue aims remove unused imports from Java/Scala code and add `UnusedImports` checkstyle rule to help developers.

## How was this patch tested?
```
./dev/lint-java
./build/sbt compile
```

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #11438 from dongjoon-hyun/SPARK-13583.
2016-03-03 10:12:32 +00:00
Sean Owen e97fc7f176 [SPARK-13423][WIP][CORE][SQL][STREAMING] Static analysis fixes for 2.x
## What changes were proposed in this pull request?

Make some cross-cutting code improvements according to static analysis. These are individually up for discussion since they exist in separate commits that can be reverted. The changes are broadly:

- Inner class should be static
- Mismatched hashCode/equals
- Overflow in compareTo
- Unchecked warnings
- Misuse of assert, vs junit.assert
- get(a) + getOrElse(b) -> getOrElse(a,b)
- Array/String .size -> .length (occasionally, -> .isEmpty / .nonEmpty) to avoid implicit conversions
- Dead code
- tailrec
- exists(_ == ) -> contains find + nonEmpty -> exists filter + size -> count
- reduce(_+_) -> sum map + flatten -> map

The most controversial may be .size -> .length simply because of its size. It is intended to avoid implicits that might be expensive in some places.

## How was the this patch tested?

Existing Jenkins unit tests.

Author: Sean Owen <sowen@cloudera.com>

Closes #11292 from srowen/SPARK-13423.
2016-03-03 09:54:09 +00:00
Reynold Xin 9e01dcc644 [SPARK-13529][BUILD] Move network/* modules into common/network-*
## What changes were proposed in this pull request?
As the title says, this moves the three modules currently in network/ into common/network-*. This removes one top level, non-user-facing folder.

## How was this patch tested?
Compilation and existing tests. We should run both SBT and Maven.

Author: Reynold Xin <rxin@databricks.com>

Closes #11409 from rxin/SPARK-13529.
2016-02-28 17:25:07 -08:00