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[SPARK-17490][SQL] Optimize SerializeFromObject() for a primitive array

Kazuaki Ishizaki authored 8 years ago

Waiting for merging #13680

This PR optimizes `SerializeFromObject()` for an primitive array. This is derived from #13758 to address one of problems by using a simple way in #13758.

The current implementation always generates `GenericArrayData` from `SerializeFromObject()` for any type of an array in a logical plan. This involves a boxing at a constructor of `GenericArrayData` when `SerializedFromObject()` has an primitive array.

This PR enables to generate `UnsafeArrayData` from `SerializeFromObject()` for a primitive array. It can avoid boxing to create an instance of `ArrayData` in the generated code by Catalyst.

This PR also generate `UnsafeArrayData` in a case for `RowEncoder.serializeFor` or `CatalystTypeConverters.createToCatalystConverter`.

Performance improvement of `SerializeFromObject()` is up to 2.0x

```
OpenJDK 64-Bit Server VM 1.8.0_91-b14 on Linux 4.4.11-200.fc22.x86_64
Intel Xeon E3-12xx v2 (Ivy Bridge)

Without this PR
Write an array in Dataset:               Best/Avg Time(ms)    Rate(M/s)   Per Row(ns)   Relative
------------------------------------------------------------------------------------------------
Int                                            556 /  608         15.1          66.3       1.0X
Double                                        1668 / 1746          5.0         198.8       0.3X

with this PR
Write an array in Dataset:               Best/Avg Time(ms)    Rate(M/s)   Per Row(ns)   Relative
------------------------------------------------------------------------------------------------
Int                                            352 /  401         23.8          42.0       1.0X
Double                                         821 /  885         10.2          97.9       0.4X
```

Here is an example program that will happen in mllib as described in [SPARK-16070](https://issues.apache.org/jira/browse/SPARK-16070

).

```
sparkContext.parallelize(Seq(Array(1, 2)), 1).toDS.map(e => e).show
```

Generated code before applying this PR

``` java
/* 039 */   protected void processNext() throws java.io.IOException {
/* 040 */     while (inputadapter_input.hasNext()) {
/* 041 */       InternalRow inputadapter_row = (InternalRow) inputadapter_input.next();
/* 042 */       int[] inputadapter_value = (int[])inputadapter_row.get(0, null);
/* 043 */
/* 044 */       Object mapelements_obj = ((Expression) references[0]).eval(null);
/* 045 */       scala.Function1 mapelements_value1 = (scala.Function1) mapelements_obj;
/* 046 */
/* 047 */       boolean mapelements_isNull = false || false;
/* 048 */       int[] mapelements_value = null;
/* 049 */       if (!mapelements_isNull) {
/* 050 */         Object mapelements_funcResult = null;
/* 051 */         mapelements_funcResult = mapelements_value1.apply(inputadapter_value);
/* 052 */         if (mapelements_funcResult == null) {
/* 053 */           mapelements_isNull = true;
/* 054 */         } else {
/* 055 */           mapelements_value = (int[]) mapelements_funcResult;
/* 056 */         }
/* 057 */
/* 058 */       }
/* 059 */       mapelements_isNull = mapelements_value == null;
/* 060 */
/* 061 */       serializefromobject_argIsNulls[0] = mapelements_isNull;
/* 062 */       serializefromobject_argValue = mapelements_value;
/* 063 */
/* 064 */       boolean serializefromobject_isNull = false;
/* 065 */       for (int idx = 0; idx < 1; idx++) {
/* 066 */         if (serializefromobject_argIsNulls[idx]) { serializefromobject_isNull = true; break; }
/* 067 */       }
/* 068 */
/* 069 */       final ArrayData serializefromobject_value = serializefromobject_isNull ? null : new org.apache.spark.sql.catalyst.util.GenericArrayData(serializefromobject_argValue);
/* 070 */       serializefromobject_holder.reset();
/* 071 */
/* 072 */       serializefromobject_rowWriter.zeroOutNullBytes();
/* 073 */
/* 074 */       if (serializefromobject_isNull) {
/* 075 */         serializefromobject_rowWriter.setNullAt(0);
/* 076 */       } else {
/* 077 */         // Remember the current cursor so that we can calculate how many bytes are
/* 078 */         // written later.
/* 079 */         final int serializefromobject_tmpCursor = serializefromobject_holder.cursor;
/* 080 */
/* 081 */         if (serializefromobject_value instanceof UnsafeArrayData) {
/* 082 */           final int serializefromobject_sizeInBytes = ((UnsafeArrayData) serializefromobject_value).getSizeInBytes();
/* 083 */           // grow the global buffer before writing data.
/* 084 */           serializefromobject_holder.grow(serializefromobject_sizeInBytes);
/* 085 */           ((UnsafeArrayData) serializefromobject_value).writeToMemory(serializefromobject_holder.buffer, serializefromobject_holder.cursor);
/* 086 */           serializefromobject_holder.cursor += serializefromobject_sizeInBytes;
/* 087 */
/* 088 */         } else {
/* 089 */           final int serializefromobject_numElements = serializefromobject_value.numElements();
/* 090 */           serializefromobject_arrayWriter.initialize(serializefromobject_holder, serializefromobject_numElements, 4);
/* 091 */
/* 092 */           for (int serializefromobject_index = 0; serializefromobject_index < serializefromobject_numElements; serializefromobject_index++) {
/* 093 */             if (serializefromobject_value.isNullAt(serializefromobject_index)) {
/* 094 */               serializefromobject_arrayWriter.setNullInt(serializefromobject_index);
/* 095 */             } else {
/* 096 */               final int serializefromobject_element = serializefromobject_value.getInt(serializefromobject_index);
/* 097 */               serializefromobject_arrayWriter.write(serializefromobject_index, serializefromobject_element);
/* 098 */             }
/* 099 */           }
/* 100 */         }
/* 101 */
/* 102 */         serializefromobject_rowWriter.setOffsetAndSize(0, serializefromobject_tmpCursor, serializefromobject_holder.cursor - serializefromobject_tmpCursor);
/* 103 */       }
/* 104 */       serializefromobject_result.setTotalSize(serializefromobject_holder.totalSize());
/* 105 */       append(serializefromobject_result);
/* 106 */       if (shouldStop()) return;
/* 107 */     }
/* 108 */   }
/* 109 */ }
```

Generated code after applying this PR

``` java
/* 035 */   protected void processNext() throws java.io.IOException {
/* 036 */     while (inputadapter_input.hasNext()) {
/* 037 */       InternalRow inputadapter_row = (InternalRow) inputadapter_input.next();
/* 038 */       int[] inputadapter_value = (int[])inputadapter_row.get(0, null);
/* 039 */
/* 040 */       Object mapelements_obj = ((Expression) references[0]).eval(null);
/* 041 */       scala.Function1 mapelements_value1 = (scala.Function1) mapelements_obj;
/* 042 */
/* 043 */       boolean mapelements_isNull = false || false;
/* 044 */       int[] mapelements_value = null;
/* 045 */       if (!mapelements_isNull) {
/* 046 */         Object mapelements_funcResult = null;
/* 047 */         mapelements_funcResult = mapelements_value1.apply(inputadapter_value);
/* 048 */         if (mapelements_funcResult == null) {
/* 049 */           mapelements_isNull = true;
/* 050 */         } else {
/* 051 */           mapelements_value = (int[]) mapelements_funcResult;
/* 052 */         }
/* 053 */
/* 054 */       }
/* 055 */       mapelements_isNull = mapelements_value == null;
/* 056 */
/* 057 */       boolean serializefromobject_isNull = mapelements_isNull;
/* 058 */       final ArrayData serializefromobject_value = serializefromobject_isNull ? null : org.apache.spark.sql.catalyst.expressions.UnsafeArrayData.fromPrimitiveArray(mapelements_value);
/* 059 */       serializefromobject_isNull = serializefromobject_value == null;
/* 060 */       serializefromobject_holder.reset();
/* 061 */
/* 062 */       serializefromobject_rowWriter.zeroOutNullBytes();
/* 063 */
/* 064 */       if (serializefromobject_isNull) {
/* 065 */         serializefromobject_rowWriter.setNullAt(0);
/* 066 */       } else {
/* 067 */         // Remember the current cursor so that we can calculate how many bytes are
/* 068 */         // written later.
/* 069 */         final int serializefromobject_tmpCursor = serializefromobject_holder.cursor;
/* 070 */
/* 071 */         if (serializefromobject_value instanceof UnsafeArrayData) {
/* 072 */           final int serializefromobject_sizeInBytes = ((UnsafeArrayData) serializefromobject_value).getSizeInBytes();
/* 073 */           // grow the global buffer before writing data.
/* 074 */           serializefromobject_holder.grow(serializefromobject_sizeInBytes);
/* 075 */           ((UnsafeArrayData) serializefromobject_value).writeToMemory(serializefromobject_holder.buffer, serializefromobject_holder.cursor);
/* 076 */           serializefromobject_holder.cursor += serializefromobject_sizeInBytes;
/* 077 */
/* 078 */         } else {
/* 079 */           final int serializefromobject_numElements = serializefromobject_value.numElements();
/* 080 */           serializefromobject_arrayWriter.initialize(serializefromobject_holder, serializefromobject_numElements, 4);
/* 081 */
/* 082 */           for (int serializefromobject_index = 0; serializefromobject_index < serializefromobject_numElements; serializefromobject_index++) {
/* 083 */             if (serializefromobject_value.isNullAt(serializefromobject_index)) {
/* 084 */               serializefromobject_arrayWriter.setNullInt(serializefromobject_index);
/* 085 */             } else {
/* 086 */               final int serializefromobject_element = serializefromobject_value.getInt(serializefromobject_index);
/* 087 */               serializefromobject_arrayWriter.write(serializefromobject_index, serializefromobject_element);
/* 088 */             }
/* 089 */           }
/* 090 */         }
/* 091 */
/* 092 */         serializefromobject_rowWriter.setOffsetAndSize(0, serializefromobject_tmpCursor, serializefromobject_holder.cursor - serializefromobject_tmpCursor);
/* 093 */       }
/* 094 */       serializefromobject_result.setTotalSize(serializefromobject_holder.totalSize());
/* 095 */       append(serializefromobject_result);
/* 096 */       if (shouldStop()) return;
/* 097 */     }
/* 098 */   }
/* 099 */ }
```

Added a test in `DatasetSuite`, `RowEncoderSuite`, and `CatalystTypeConvertersSuite`

Author: Kazuaki Ishizaki <ishizaki@jp.ibm.com>

Closes #15044 from kiszk/SPARK-17490.

(cherry picked from commit 19cf2080)
Signed-off-by: Herman van Hovell <hvanhovell@databricks.com>

9873d57f

9873d57f 8 years ago

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Apache Spark

Spark is a fast and general cluster computing system for Big Data. It provides high-level APIs in Scala, Java, Python, and R, and an optimized engine that supports general computation graphs for data analysis. It also supports a rich set of higher-level tools including Spark SQL for SQL and DataFrames, MLlib for machine learning, GraphX for graph processing, and Spark Streaming for stream processing.

http://spark.apache.org/

Online Documentation

You can find the latest Spark documentation, including a programming guide, on the project web page and project wiki. This README file only contains basic setup instructions.

Building Spark

Spark is built using Apache Maven. To build Spark and its example programs, run:

build/mvn -DskipTests clean package

(You do not need to do this if you downloaded a pre-built package.)

You can build Spark using more than one thread by using the -T option with Maven, see "Parallel builds in Maven 3". More detailed documentation is available from the project site, at "Building Spark". For developing Spark using an IDE, see Eclipse and IntelliJ.

Interactive Scala Shell

The easiest way to start using Spark is through the Scala shell:

./bin/spark-shell

Try the following command, which should return 1000:

scala> sc.parallelize(1 to 1000).count()

Interactive Python Shell

Alternatively, if you prefer Python, you can use the Python shell:

./bin/pyspark

And run the following command, which should also return 1000:

>>> sc.parallelize(range(1000)).count()

Example Programs

Spark also comes with several sample programs in the examples directory. To run one of them, use ./bin/run-example <class> [params]. For example:

./bin/run-example SparkPi

will run the Pi example locally.

You can set the MASTER environment variable when running examples to submit examples to a cluster. This can be a mesos:// or spark:// URL, "yarn" to run on YARN, and "local" to run locally with one thread, or "local[N]" to run locally with N threads. You can also use an abbreviated class name if the class is in the examples package. For instance:

MASTER=spark://host:7077 ./bin/run-example SparkPi

Many of the example programs print usage help if no params are given.

Running Tests

Testing first requires building Spark. Once Spark is built, tests can be run using:

./dev/run-tests

Please see the guidance on how to run tests for a module, or individual tests.

A Note About Hadoop Versions

Spark uses the Hadoop core library to talk to HDFS and other Hadoop-supported storage systems. Because the protocols have changed in different versions of Hadoop, you must build Spark against the same version that your cluster runs.

Please refer to the build documentation at "Specifying the Hadoop Version" for detailed guidance on building for a particular distribution of Hadoop, including building for particular Hive and Hive Thriftserver distributions.

Configuration

Please refer to the Configuration Guide in the online documentation for an overview on how to configure Spark.

## Contributing

Please review the Contribution to Spark wiki for information on how to get started contributing to the project.