[GitHub] spark pull request #15063: [SPARK-17463][Core]Make CollectionAccumulator and...

[asfgit]

Github user asfgit closed the pull request at:

https://github.com/apache/spark/pull/15063


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

-
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

[GitHub] spark pull request #15063: [SPARK-17463][Core]Make CollectionAccumulator and...

[zsxwing]

Github user zsxwing commented on a diff in the pull request:

https://github.com/apache/spark/pull/15063#discussion_r78433588
  
--- Diff: 
sql/core/src/main/scala/org/apache/spark/sql/execution/debug/package.scala ---
@@ -107,18 +109,20 @@ package object debug {
   case class DebugExec(child: SparkPlan) extends UnaryExecNode with 
CodegenSupport {
 def output: Seq[Attribute] = child.output
 
-class SetAccumulator[T] extends AccumulatorV2[T, HashSet[T]] {
-  private val _set = new HashSet[T]()
+class SetAccumulator[T] extends AccumulatorV2[T, java.util.Set[T]] {
+  private val _set = Collections.synchronizedSet(new 
java.util.HashSet[T]())
--- End diff --

For Java serialization, it's synchronized. See: 
http://www.grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/8u40-b25/java/util/Collections.java#2080

Do we use Kryo to serialize Heartbeat?


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

-
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

[GitHub] spark pull request #15063: [SPARK-17463][Core]Make CollectionAccumulator and...

[JoshRosen]

Github user JoshRosen commented on a diff in the pull request:

https://github.com/apache/spark/pull/15063#discussion_r78432833
  
--- Diff: 
sql/core/src/main/scala/org/apache/spark/sql/execution/debug/package.scala ---
@@ -107,18 +109,20 @@ package object debug {
   case class DebugExec(child: SparkPlan) extends UnaryExecNode with 
CodegenSupport {
 def output: Seq[Attribute] = child.output
 
-class SetAccumulator[T] extends AccumulatorV2[T, HashSet[T]] {
-  private val _set = new HashSet[T]()
+class SetAccumulator[T] extends AccumulatorV2[T, java.util.Set[T]] {
+  private val _set = Collections.synchronizedSet(new 
java.util.HashSet[T]())
--- End diff --

If you use `Collections.synchronized*`, will serialization of those objects 
also be thread-safe (i.e. will `writeObject` synchronize properly)? What about 
if Kryo is used?


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

-
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

[GitHub] spark pull request #15063: [SPARK-17463][Core]Make CollectionAccumulator and...

[zsxwing]

GitHub user zsxwing opened a pull request:

https://github.com/apache/spark/pull/15063

[SPARK-17463][Core]Make CollectionAccumulator and SetAccumulator's value 
can be read thread-safely

## What changes were proposed in this pull request?

Make CollectionAccumulator and SetAccumulator's value can be read 
thread-safely to fix the ConcurrentModificationException reported in 
[JIRA](https://issues.apache.org/jira/browse/SPARK-17463).

## How was this patch tested?

Existing tests.

You can merge this pull request into a Git repository by running:

$ git pull https://github.com/zsxwing/spark SPARK-17463

Alternatively you can review and apply these changes as the patch at:

https://github.com/apache/spark/pull/15063.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 #15063


commit 4b8c277ebb1c8ff966e6d3c2676dfc34a1f0c483
Author: Shixiong Zhu 
Date:   2016-09-12T17:45:35Z

Make CollectionAccumulator and SetAccumulator's value can be read 
thread-safely




---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

-
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org