[SPARK-12895][SPARK-12896] Migrate TaskMetrics to accumulators #10835
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commit 269031f Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 16:33:12 2016 -0800 Remove unused method commit c04b5df Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 16:13:08 2016 -0800 Review comments commit d2e4e23 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 14:42:19 2016 -0800 One more commit 202d48e Merge: e99b9af 4f11e3f Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 14:27:47 2016 -0800 Merge branch 'master' of github.com:apache/spark into get-or-create-metrics commit e99b9af Merge: 34c7ce5 b8cb548 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 13:56:41 2016 -0800 Merge branch 'master' of github.com:apache/spark into get-or-create-metrics Conflicts: core/src/main/scala/org/apache/spark/CacheManager.scala core/src/main/scala/org/apache/spark/memory/StorageMemoryPool.scala core/src/test/scala/org/apache/spark/CacheManagerSuite.scala commit 34c7ce5 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 12:46:42 2016 -0800 Hide updatedBlocks commit ad094f0 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 12:30:59 2016 -0800 Clean up JsonProtocol This commit collapsed 10 methods into 2. The 8 that were inlined were only used in 1 place each, and the body of each was quite small. The additional level of abstraction did not add much value and made the code verbose. commit 0785984 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 12:20:28 2016 -0800 Replace set with register JsonProtocol remains the only place where we still call set on each of the *Metrics classes. commit b9d7fbf Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 12:10:17 2016 -0800 Clean up places where we set OutputMetrics Note: there's one remaining place, which is JsonProtocol. commit 62c96e1 Author: Andrew Or <andrew@databricks.com> Date: Mon Jan 18 11:50:04 2016 -0800 Add register* methods (get or create)
Previously we would always zero out an accumulator when we deserialize it. Certainly we don't want to do that on the driver. The changes in this commit are temporary and will be reverted in SPARK-12896.
Tests don't pass yet, obviously...
+ fix tests, which are still failing
... by setting it to zero on the executors, always.
…e-accums Conflicts: core/src/main/scala/org/apache/spark/CacheManager.scala core/src/main/scala/org/apache/spark/executor/Executor.scala core/src/main/scala/org/apache/spark/executor/ShuffleWriteMetrics.scala core/src/main/scala/org/apache/spark/executor/TaskMetrics.scala core/src/main/scala/org/apache/spark/shuffle/sort/SortShuffleWriter.scala core/src/main/scala/org/apache/spark/util/JsonProtocol.scala core/src/test/scala/org/apache/spark/ui/jobs/JobProgressListenerSuite.scala core/src/test/scala/org/apache/spark/util/JsonProtocolSuite.scala
Also add some useful error printing if things don't match.
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Test build #49702 has finished for PR 10835 at commit
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Test build #49718 has finished for PR 10835 at commit
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We never updated the original ShuffleReadMetrics accumulators; we were updating a copy.
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Test build #49724 has finished for PR 10835 at commit
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Test build #49729 has finished for PR 10835 at commit
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Test build #49732 has finished for PR 10835 at commit
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| @@ -212,6 +212,8 @@ class HadoopRDD[K, V]( | |||
| logInfo("Input split: " + split.inputSplit) | |||
| val jobConf = getJobConf() | |||
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| // TODO: there is a lot of duplicate code between this and NewHadoopRDD and SqlNewHadoopRDD | |||
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Yep, SQLNewHadoopRDD started as a copy of NewHadoopRDD and then diverged some more. It would be great to try to clean this up at some point.
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According to Reviewable I'm all caught up with the latest changes. This looks like it's in really good shape to me; I only had a few very minor comments upthread, plus one or two clarifying questions (I think everything is fine, but just wanted to double-check my understanding before a final sign-off). I think we're on track to get this by end-of-day tomorrow, if not earlier. |
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retest this please |
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Test build #50110 has finished for PR 10835 at commit
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| if (!stageIdToStage.contains(task.stageId)) { | ||
| // Skip all the actions if the stage has been cancelled. | ||
| return | ||
| } | ||
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| listenerBus.post(SparkListenerTaskEnd( |
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Actually, I guess the old logic was kinda convoluted in the sense that it would report failures of cancelled stages' tasks to the listener bus, but not completions of successes. The new behavior of skipping the listener event for all tasks from cancelled stages, not just successful ones, makes more sense.
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actually, it's failing tests now and I don't know why. For simplicity I'm just going to revert this change since it's largely orthogonal and add a comment that the old comment was wrong. We can fix it later if we want to.
| @@ -1125,24 +1130,31 @@ class DAGScheduler( | |||
| event.taskInfo.attemptNumber, // this is a task attempt number | |||
| event.reason) | |||
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| // The success case is dealt with separately below, since we need to compute accumulator | |||
| // updates before posting. | |||
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by the way this comment isn't even true. I think this whole "post only failed tasks of cancelled stages" behavior is not intentional to begin with. I tried to look into this but there are 30 layers of indirection so I just gave up. Let's tackle this separately (if it actually matters).
Looks like previous changes accidentally broke an unspoken contract in posting task end events. There's no documentation anywhere so it's unclear what the right behavior is. For simplicity I will revert this part of the patch and maybe fix it later.
... by ignoring the failing tests. These tests were non-deterministically failing only because exceptions in job end callbacks weren't propagated properly due to a race condition. In terms of the failing tests themselves, they don't actually correctly test what they intend to. Fixing this should be done in a follow-up patch.
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retest this please |
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@JoshRosen I believe I addressed all of your comments. The latest commit should pass tests. There are a few things I would like to do on my end that shouldn't block on the merging of this patch:
If this patch looks good to you and it passes tests, feel free to merge it. I'll keep working on these things in the mean time. |
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Test build #50163 has finished for PR 10835 at commit
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I'm going to merge this now and we'll deal with those other tasks in followup patches. Thanks! |
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I have compiled a list of breaking ExceptionFailure:
InputMetrics:
OutputMetrics:
ShuffleReadMetrics:
ShuffleWriteMetrics:
TaskMetrics:
AccumulableInfo:
SparkListenerTaskEnd:
SparkListenerExecutorMetricsUpdate:
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I was able to verify that the changes in |
This is an existing issue uncovered recently by #10835. The reason for the exception was because the `SQLHistoryListener` gets all sorts of accumulators, not just the ones that represent SQL metrics. For example, the listener gets the `internal.metrics.shuffleRead.remoteBlocksFetched`, which is an Int, then it proceeds to cast the Int to a Long, which fails. The fix is to mark accumulators representing SQL metrics using some internal metadata. Then we can identify which ones are SQL metrics and only process those in the `SQLHistoryListener`. Author: Andrew Or <andrew@databricks.com> Closes #10971 from andrewor14/fix-sql-history.
This issue is causing tests to fail consistently in master with Hadoop 2.6 / 2.7. This is because for Hadoop 2.5+ we overwrite existing values of `InputMetrics#bytesRead` in each call to `HadoopRDD#compute`. In the case of coalesce, e.g. ``` sc.textFile(..., 4).coalesce(2).count() ``` we will call `compute` multiple times in the same task, overwriting `bytesRead` values from previous calls to `compute`. For a regression test, see `InputOutputMetricsSuite.input metrics for old hadoop with coalesce`. I did not add a new regression test because it's impossible without significant refactoring; there's a lot of existing duplicate code in this corner of Spark. This was caused by #10835. Author: Andrew Or <andrew@databricks.com> Closes #10973 from andrewor14/fix-input-metrics-coalesce.
See [JIRA](https://issues.apache.org/jira/browse/SPARK-13344) for more detail. This was caused by #10835. Author: Andrew Or <andrew@databricks.com> Closes #11222 from andrewor14/fix-test-accum-exceptions.
The high level idea is that instead of having the executors send both accumulator updates and TaskMetrics, we should have them send only accumulator updates. This eliminates the need to maintain both code paths since one can be implemented in terms of the other. This effort is split into two parts:
SPARK-12895: Implement TaskMetrics using accumulators. TaskMetrics is basically just a bunch of accumulable fields. This patch makes TaskMetrics a syntactic wrapper around a collection of accumulators so we don't need to send TaskMetrics from the executors to the driver.
SPARK-12896: Send only accumulator updates to the driver. Now that TaskMetrics are expressed in terms of accumulators, we can capture all TaskMetrics values if we just send accumulator updates from the executors to the driver. This completes the parent issue SPARK-10620.
While an effort has been made to preserve as much of the public API as possible, there were a few known breaking @DeveloperAPI changes that would be very awkward to maintain. I will gather the full list shortly and post it here.
Note: This was once part of #10717. This patch is split out into its own patch from there to make it easier for others to review. Other smaller pieces of already been merged into master.