[
https://issues.apache.org/jira/browse/SPARK-47177?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Ziqi Liu updated SPARK-47177:
-----------------------------
Description:
AQE plan is expected to display final plan after execution. This is not true
for cached SQL plan: it will show the initial plan instead. This behavior
change is introduced in [https://github.com/apache/spark/pull/40812] it tried
to fix the concurrency issue with cached plan.
*In short, the plan used to executed and the plan used to explain is not the
same instance, thus causing the inconsistency.*
I don't have a clear idea how yet
* maybe we just a coarse granularity lock in explain?
* make innerChildren a function: clone the initial plan, every time checked
for whether the original AQE plan is finalized (making the final flag atomic
first, of course), if no return the cloned initial plan, if it's finalized,
clone the final plan and return that one. But still this won't be able to
reflect the AQE plan in real time, in a concurrent situation, but at least we
have initial version and final version.
A simple repro:
{code:java}
d1 = spark.range(1000).withColumn("key", expr("id %
100")).groupBy("key").agg({"key": "count"})
cached_d2 = d1.cache()
df = cached_d2.filter("key > 10")
df.collect() {code}
{code:java}
>>> df.explain()
== Physical Plan ==
AdaptiveSparkPlan isFinalPlan=true
+- == Final Plan ==
*(1) Filter (isnotnull(key#4L) AND (key#4L > 10))
+- TableCacheQueryStage 0
+- InMemoryTableScan [key#4L, count(key)#10L], [isnotnull(key#4L),
(key#4L > 10)]
+- InMemoryRelation [key#4L, count(key)#10L], StorageLevel(disk,
memory, deserialized, 1 replicas)
+- AdaptiveSparkPlan isFinalPlan=false
+- HashAggregate(keys=[key#4L], functions=[count(key#4L)])
+- Exchange hashpartitioning(key#4L, 200),
ENSURE_REQUIREMENTS, [plan_id=24]
+- HashAggregate(keys=[key#4L],
functions=[partial_count(key#4L)])
+- Project [(id#2L % 100) AS key#4L]
+- Range (0, 1000, step=1, splits=10)
+- == Initial Plan ==
Filter (isnotnull(key#4L) AND (key#4L > 10))
+- InMemoryTableScan [key#4L, count(key)#10L], [isnotnull(key#4L), (key#4L >
10)]
+- InMemoryRelation [key#4L, count(key)#10L], StorageLevel(disk,
memory, deserialized, 1 replicas)
+- AdaptiveSparkPlan isFinalPlan=false
+- HashAggregate(keys=[key#4L], functions=[count(key#4L)])
+- Exchange hashpartitioning(key#4L, 200),
ENSURE_REQUIREMENTS, [plan_id=24]
+- HashAggregate(keys=[key#4L],
functions=[partial_count(key#4L)])
+- Project [(id#2L % 100) AS key#4L]
+- Range (0, 1000, step=1, splits=10){code}
was:
AQE plan is expected to display final plan after execution. This is not true
for cached SQL plan: it will show the initial plan instead. This behavior
change is introduced in [https://github.com/apache/spark/pull/40812] it tried
to fix the concurrency issue with cached plan.
*In short, the plan used to executed and the plan used to explain is not the
same instance, thus causing the inconsistency.*
I don't have a clear idea how yet
* maybe we just a coarse granularity lock in explain?
* make innerChildren a function: clone the initial plan, every time checked
for whether the original AQE plan is finalized (making the final flag atomic
first, of course), if no return the cloned initial plan, if it's finalized,
clone the final plan and return that one. But still this won't be able to
reflect the AQE plan in real time, in a concurrent situation, but at least we
have initial version and final version.
A simple repro:
{code:java}
d1 = spark.range(1000).withColumn("key", expr("id %
100")).groupBy("key").agg({"key": "count"})
cached_d2 = d1.cache()
df = cached_d2.withColumn("key2", expr("key %
10")).groupBy("key2").agg({"key2": "count"})
df.collect() {code}
{code:java}
>>> df.explain()
== Physical Plan ==
AdaptiveSparkPlan isFinalPlan=true
+- == Final Plan ==
*(2) HashAggregate(keys=[key2#36L], functions=[count(key2#36L)])
+- AQEShuffleRead coalesced
+- ShuffleQueryStage 1
+- Exchange hashpartitioning(key2#36L, 200), ENSURE_REQUIREMENTS,
[plan_id=83]
+- *(1) HashAggregate(keys=[key2#36L],
functions=[partial_count(key2#36L)])
+- *(1) Project [(key#27L % 10) AS key2#36L]
+- TableCacheQueryStage 0
+- InMemoryTableScan [key#27L]
+- InMemoryRelation [key#27L, count(key)#33L],
StorageLevel(disk, memory, deserialized, 1 replicas)
+- AdaptiveSparkPlan isFinalPlan=false
+- HashAggregate(keys=[key#4L],
functions=[count(key#4L)])
+- Exchange hashpartitioning(key#4L,
200), ENSURE_REQUIREMENTS, [plan_id=33]
+- HashAggregate(keys=[key#4L],
functions=[partial_count(key#4L)])
+- Project [(id#2L % 100) AS
key#4L]
+- Range (0, 1000, step=1,
splits=10)
+- == Initial Plan ==
HashAggregate(keys=[key2#36L], functions=[count(key2#36L)])
+- Exchange hashpartitioning(key2#36L, 200), ENSURE_REQUIREMENTS,
[plan_id=30]
+- HashAggregate(keys=[key2#36L], functions=[partial_count(key2#36L)])
+- Project [(key#27L % 10) AS key2#36L]
+- InMemoryTableScan [key#27L]
+- InMemoryRelation [key#27L, count(key)#33L],
StorageLevel(disk, memory, deserialized, 1 replicas)
+- AdaptiveSparkPlan isFinalPlan=false
+- HashAggregate(keys=[key#4L],
functions=[count(key#4L)])
+- Exchange hashpartitioning(key#4L, 200),
ENSURE_REQUIREMENTS, [plan_id=33]
+- HashAggregate(keys=[key#4L],
functions=[partial_count(key#4L)])
+- Project [(id#2L % 100) AS key#4L]
+- Range (0, 1000, step=1, splits=10)
{code}
> Cached SQL plan do not display final AQE plan in explain string
> ---------------------------------------------------------------
>
> Key: SPARK-47177
> URL: https://issues.apache.org/jira/browse/SPARK-47177
> Project: Spark
> Issue Type: Bug
> Components: Spark Core
> Affects Versions: 3.4.2, 3.5.0, 4.0.0, 3.5.1, 3.5.2
> Reporter: Ziqi Liu
> Priority: Major
> Labels: pull-request-available
>
> AQE plan is expected to display final plan after execution. This is not true
> for cached SQL plan: it will show the initial plan instead. This behavior
> change is introduced in [https://github.com/apache/spark/pull/40812] it tried
> to fix the concurrency issue with cached plan.
> *In short, the plan used to executed and the plan used to explain is not the
> same instance, thus causing the inconsistency.*
>
> I don't have a clear idea how yet
> * maybe we just a coarse granularity lock in explain?
> * make innerChildren a function: clone the initial plan, every time checked
> for whether the original AQE plan is finalized (making the final flag atomic
> first, of course), if no return the cloned initial plan, if it's finalized,
> clone the final plan and return that one. But still this won't be able to
> reflect the AQE plan in real time, in a concurrent situation, but at least we
> have initial version and final version.
>
> A simple repro:
> {code:java}
> d1 = spark.range(1000).withColumn("key", expr("id %
> 100")).groupBy("key").agg({"key": "count"})
> cached_d2 = d1.cache()
> df = cached_d2.filter("key > 10")
> df.collect() {code}
> {code:java}
> >>> df.explain()
> == Physical Plan ==
> AdaptiveSparkPlan isFinalPlan=true
> +- == Final Plan ==
> *(1) Filter (isnotnull(key#4L) AND (key#4L > 10))
> +- TableCacheQueryStage 0
> +- InMemoryTableScan [key#4L, count(key)#10L], [isnotnull(key#4L),
> (key#4L > 10)]
> +- InMemoryRelation [key#4L, count(key)#10L], StorageLevel(disk,
> memory, deserialized, 1 replicas)
> +- AdaptiveSparkPlan isFinalPlan=false
> +- HashAggregate(keys=[key#4L],
> functions=[count(key#4L)])
> +- Exchange hashpartitioning(key#4L, 200),
> ENSURE_REQUIREMENTS, [plan_id=24]
> +- HashAggregate(keys=[key#4L],
> functions=[partial_count(key#4L)])
> +- Project [(id#2L % 100) AS key#4L]
> +- Range (0, 1000, step=1, splits=10)
> +- == Initial Plan ==
> Filter (isnotnull(key#4L) AND (key#4L > 10))
> +- InMemoryTableScan [key#4L, count(key)#10L], [isnotnull(key#4L), (key#4L
> > 10)]
> +- InMemoryRelation [key#4L, count(key)#10L], StorageLevel(disk,
> memory, deserialized, 1 replicas)
> +- AdaptiveSparkPlan isFinalPlan=false
> +- HashAggregate(keys=[key#4L], functions=[count(key#4L)])
> +- Exchange hashpartitioning(key#4L, 200),
> ENSURE_REQUIREMENTS, [plan_id=24]
> +- HashAggregate(keys=[key#4L],
> functions=[partial_count(key#4L)])
> +- Project [(id#2L % 100) AS key#4L]
> +- Range (0, 1000, step=1, splits=10){code}
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