spark-instrumented-optimizer/python
Liang-Chi Hsieh 1e35e96930 [SPARK-17817] [PYSPARK] [FOLLOWUP] PySpark RDD Repartitioning Results in Highly Skewed Partition Sizes
## What changes were proposed in this pull request?

This change is a followup for #15389 which calls `_to_java_object_rdd()` to solve this issue. Due to the concern of the possible expensive cost of the call, we can choose to decrease the batch size to solve this issue too.

Simple benchmark:

    import time
    num_partitions = 20000
    a = sc.parallelize(range(int(1e6)), 2)
    start = time.time()
    l = a.repartition(num_partitions).glom().map(len).collect()
    end = time.time()
    print(end - start)

Before: 419.447577953
_to_java_object_rdd(): 421.916361094
decreasing the batch size: 423.712255955

## How was this patch tested?

Jenkins tests.

Author: Liang-Chi Hsieh <viirya@gmail.com>

Closes #15445 from viirya/repartition-batch-size.
2016-10-18 14:25:10 -07:00
..
docs [SPARK-16781][PYSPARK] java launched by PySpark as gateway may not be the same java used in the spark environment 2016-08-24 20:04:09 +01:00
lib [SPARK-16781][PYSPARK] java launched by PySpark as gateway may not be the same java used in the spark environment 2016-08-24 20:04:09 +01:00
pyspark [SPARK-17817] [PYSPARK] [FOLLOWUP] PySpark RDD Repartitioning Results in Highly Skewed Partition Sizes 2016-10-18 14:25:10 -07:00
test_support [SPARK-17585][PYSPARK][CORE] PySpark SparkContext.addFile supports adding files recursively 2016-09-21 01:37:03 -07:00
.gitignore [SPARK-3946] gitignore in /python includes wrong directory 2014-10-14 14:09:39 -07:00
pylintrc [SPARK-13596][BUILD] Move misc top-level build files into appropriate subdirs 2016-03-07 14:48:02 -08:00
run-tests [SPARK-8583] [SPARK-5482] [BUILD] Refactor python/run-tests to integrate with dev/run-tests module system 2015-06-27 20:24:34 -07:00
run-tests.py [SPARK-13579][BUILD] Stop building the main Spark assembly. 2016-04-04 16:52:22 -07:00