Repository: spark Updated Branches: refs/heads/master 96786e3ee -> edd3cd477
[SPARK-4715][Core] Make sure tryToAcquire won't return a negative value ShuffleMemoryManager.tryToAcquire may return a negative value. The unit test demonstrates this bug. It will output `0 did not equal -200 granted is negative`. Author: zsxwing <[email protected]> Closes #3575 from zsxwing/SPARK-4715 and squashes the following commits: a193ae6 [zsxwing] Make sure tryToAcquire won't return a negative value Project: http://git-wip-us.apache.org/repos/asf/spark/repo Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/edd3cd47 Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/edd3cd47 Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/edd3cd47 Branch: refs/heads/master Commit: edd3cd477c9d6016bd977c2fa692fdeff5a6e198 Parents: 96786e3 Author: zsxwing <[email protected]> Authored: Wed Dec 3 12:19:40 2014 -0800 Committer: Andrew Or <[email protected]> Committed: Wed Dec 3 12:19:40 2014 -0800 ---------------------------------------------------------------------- .../spark/shuffle/ShuffleMemoryManager.scala | 5 +++-- .../spark/shuffle/ShuffleMemoryManagerSuite.scala | 17 ++++++++++++++++- 2 files changed, 19 insertions(+), 3 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/spark/blob/edd3cd47/core/src/main/scala/org/apache/spark/shuffle/ShuffleMemoryManager.scala ---------------------------------------------------------------------- diff --git a/core/src/main/scala/org/apache/spark/shuffle/ShuffleMemoryManager.scala b/core/src/main/scala/org/apache/spark/shuffle/ShuffleMemoryManager.scala index ee91a36..3bcc717 100644 --- a/core/src/main/scala/org/apache/spark/shuffle/ShuffleMemoryManager.scala +++ b/core/src/main/scala/org/apache/spark/shuffle/ShuffleMemoryManager.scala @@ -66,8 +66,9 @@ private[spark] class ShuffleMemoryManager(maxMemory: Long) extends Logging { val curMem = threadMemory(threadId) val freeMemory = maxMemory - threadMemory.values.sum - // How much we can grant this thread; don't let it grow to more than 1 / numActiveThreads - val maxToGrant = math.min(numBytes, (maxMemory / numActiveThreads) - curMem) + // How much we can grant this thread; don't let it grow to more than 1 / numActiveThreads; + // don't let it be negative + val maxToGrant = math.min(numBytes, math.max(0, (maxMemory / numActiveThreads) - curMem)) if (curMem < maxMemory / (2 * numActiveThreads)) { // We want to let each thread get at least 1 / (2 * numActiveThreads) before blocking; http://git-wip-us.apache.org/repos/asf/spark/blob/edd3cd47/core/src/test/scala/org/apache/spark/shuffle/ShuffleMemoryManagerSuite.scala ---------------------------------------------------------------------- diff --git a/core/src/test/scala/org/apache/spark/shuffle/ShuffleMemoryManagerSuite.scala b/core/src/test/scala/org/apache/spark/shuffle/ShuffleMemoryManagerSuite.scala index d31bc22..e0e646f 100644 --- a/core/src/test/scala/org/apache/spark/shuffle/ShuffleMemoryManagerSuite.scala +++ b/core/src/test/scala/org/apache/spark/shuffle/ShuffleMemoryManagerSuite.scala @@ -159,7 +159,7 @@ class ShuffleMemoryManagerSuite extends FunSuite with Timeouts { test("threads can block to get at least 1 / 2N memory") { // t1 grabs 1000 bytes and then waits until t2 is ready to make a request. It sleeps - // for a bit and releases 250 bytes, which should then be greanted to t2. Further requests + // for a bit and releases 250 bytes, which should then be granted to t2. Further requests // by t2 will return false right away because it now has 1 / 2N of the memory. val manager = new ShuffleMemoryManager(1000L) @@ -291,4 +291,19 @@ class ShuffleMemoryManagerSuite extends FunSuite with Timeouts { assert(state.t2WaitTime > 200, s"t2 waited less than 200 ms (${state.t2WaitTime})") } } + + test("threads should not be granted a negative size") { + val manager = new ShuffleMemoryManager(1000L) + manager.tryToAcquire(700L) + + val latch = new CountDownLatch(1) + startThread("t1") { + manager.tryToAcquire(300L) + latch.countDown() + } + latch.await() // Wait until `t1` calls `tryToAcquire` + + val granted = manager.tryToAcquire(300L) + assert(0 === granted, "granted is negative") + } } --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
