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Posted to issues@spark.apache.org by "Karuppayya (Jira)" <ji...@apache.org> on 2020/05/28 06:01:00 UTC
[jira] [Updated] (SPARK-31850) DetermineTableStats rules computes
stats multiple time for same table
[ https://issues.apache.org/jira/browse/SPARK-31850?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Karuppayya updated SPARK-31850:
-------------------------------
Description:
DetermineTableStats rules computes stats multiple time for same table.
There are few rules which invoke
org.apache.spark.sql.catalyst.analysis.Analyzer#executeSameContext
* The above method cause the logical plan to go through the analysis phase multiple times
* The above method is invoked as a part of rule(s) which is part of a batch which run till *Fixed point* which implies that that the analysis phase can run multiple time
* example: [https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138 |https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138]
* This is cause of concern especially in *DetermineTableStats* rule, where the computation of stats can be expensive for a large table(And also it happens multiple time due to the fixed point nature of batch from which analysis is triggered)
Repro steps
{code:java}
spark.sql("create table c(id INT, name STRING) STORED AS PARQUET")
val df = spark.sql("select count(id) id from c group by name order by id " )
df.queryExecution.analyzed
{code}
Note:
* There is no log line in DetermineTableStats to indicate that stats compute happened. Need to add a log line or use a debugger
* The above can be repro-ed with first query on a created table.
was:
DetermineTableStats rules computes stats multiple time.
There are few rules which invoke
org.apache.spark.sql.catalyst.analysis.Analyzer#executeSameContext
* The above method cause the logical plan to go through the analysis phase multiple times
* The above method is invoked as a part of rule(s) which is part of a batch which run till *Fixed point* which implies that that the analysis phase can run multiple time
* example: [https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138 |https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138]
* This is cause of concern especially in *DetermineTableStats* rule, where the computation of stats can be expensive for a large table(And also it happens multiple time due to the fixed point nature of batch from which analysis is triggered)
Repro steps
{code:java}
spark.sql("create table c(id INT, name STRING) STORED AS PARQUET")
val df = spark.sql("select count(id) id from c group by name order by id " )
df.queryExecution.analyzed
{code}
Note:
* There is no log line in DetermineTableStats to indicate that stats compute happened. Need to add a log line or use a debugger
* The above can be repro-ed with first query on a created table.
Summary: DetermineTableStats rules computes stats multiple time for same table (was: DetermineTableStats rules computes stats multiple time)
> DetermineTableStats rules computes stats multiple time for same table
> ---------------------------------------------------------------------
>
> Key: SPARK-31850
> URL: https://issues.apache.org/jira/browse/SPARK-31850
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 3.0.0
> Reporter: Karuppayya
> Priority: Major
>
> DetermineTableStats rules computes stats multiple time for same table.
> There are few rules which invoke
> org.apache.spark.sql.catalyst.analysis.Analyzer#executeSameContext
> * The above method cause the logical plan to go through the analysis phase multiple times
> * The above method is invoked as a part of rule(s) which is part of a batch which run till *Fixed point* which implies that that the analysis phase can run multiple time
> * example: [https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138 |https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2138]
> * This is cause of concern especially in *DetermineTableStats* rule, where the computation of stats can be expensive for a large table(And also it happens multiple time due to the fixed point nature of batch from which analysis is triggered)
>
> Repro steps
> {code:java}
>
> spark.sql("create table c(id INT, name STRING) STORED AS PARQUET")
> val df = spark.sql("select count(id) id from c group by name order by id " )
> df.queryExecution.analyzed
> {code}
> Note:
> * There is no log line in DetermineTableStats to indicate that stats compute happened. Need to add a log line or use a debugger
> * The above can be repro-ed with first query on a created table.
>
>
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