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author | oraviv <oraviv@paypal.com> | 2016-07-13 14:47:08 +0100 |
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committer | Sean Owen <sowen@cloudera.com> | 2016-07-13 14:47:08 +0100 |
commit | ea06e4ef34c860219a9aeec81816ef53ada96253 (patch) | |
tree | 32fe745a7941c76a6044d12933dac5c6a4772cdf /mllib | |
parent | 51ade51a9fd64fc2fe651c505a286e6f29f59d40 (diff) | |
download | spark-ea06e4ef34c860219a9aeec81816ef53ada96253.tar.gz spark-ea06e4ef34c860219a9aeec81816ef53ada96253.tar.bz2 spark-ea06e4ef34c860219a9aeec81816ef53ada96253.zip |
[SPARK-16469] enhanced simulate multiply
## What changes were proposed in this pull request?
We have a use case of multiplying very big sparse matrices. we have about 1000x1000 distributed block matrices multiplication and the simulate multiply goes like O(n^4) (n being 1000). it takes about 1.5 hours. We modified it slightly with classical hashmap and now run in about 30 seconds O(n^2).
## How was this patch tested?
We have added a performance test and verified the reduced time.
Author: oraviv <oraviv@paypal.com>
Closes #14068 from uzadude/master.
Diffstat (limited to 'mllib')
-rw-r--r-- | mllib/src/main/scala/org/apache/spark/mllib/linalg/distributed/BlockMatrix.scala | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/mllib/src/main/scala/org/apache/spark/mllib/linalg/distributed/BlockMatrix.scala b/mllib/src/main/scala/org/apache/spark/mllib/linalg/distributed/BlockMatrix.scala index 639295c695..9782350587 100644 --- a/mllib/src/main/scala/org/apache/spark/mllib/linalg/distributed/BlockMatrix.scala +++ b/mllib/src/main/scala/org/apache/spark/mllib/linalg/distributed/BlockMatrix.scala @@ -426,16 +426,21 @@ class BlockMatrix @Since("1.3.0") ( partitioner: GridPartitioner): (BlockDestinations, BlockDestinations) = { val leftMatrix = blockInfo.keys.collect() // blockInfo should already be cached val rightMatrix = other.blocks.keys.collect() + + val rightCounterpartsHelper = rightMatrix.groupBy(_._1).mapValues(_.map(_._2)) val leftDestinations = leftMatrix.map { case (rowIndex, colIndex) => - val rightCounterparts = rightMatrix.filter(_._1 == colIndex) - val partitions = rightCounterparts.map(b => partitioner.getPartition((rowIndex, b._2))) + val rightCounterparts = rightCounterpartsHelper.getOrElse(colIndex, Array()) + val partitions = rightCounterparts.map(b => partitioner.getPartition((rowIndex, b))) ((rowIndex, colIndex), partitions.toSet) }.toMap + + val leftCounterpartsHelper = leftMatrix.groupBy(_._2).mapValues(_.map(_._1)) val rightDestinations = rightMatrix.map { case (rowIndex, colIndex) => - val leftCounterparts = leftMatrix.filter(_._2 == rowIndex) - val partitions = leftCounterparts.map(b => partitioner.getPartition((b._1, colIndex))) + val leftCounterparts = leftCounterpartsHelper.getOrElse(rowIndex, Array()) + val partitions = leftCounterparts.map(b => partitioner.getPartition((b, colIndex))) ((rowIndex, colIndex), partitions.toSet) }.toMap + (leftDestinations, rightDestinations) } |