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What changes were proposed in this pull request?

Why are the changes needed?

Does this PR introduce any user-facing change?

How was this patch tested?

sarutak and others added 11 commits October 4, 2020 16:11
…ocalityPlacementStrategySuite for Java 11 with sbt

### What changes were proposed in this pull request?

This PR fixes an issue that a test in `LocalityPlacementStrategySuite` fails with Java 11 due to `StackOverflowError`.

```
[info] - handle large number of containers and tasks (SPARK-18750) *** FAILED *** (170 milliseconds)
[info]   StackOverflowError should not be thrown; however, got:
[info]
[info]   java.lang.StackOverflowError
[info]          at java.base/java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1012)
[info]          at java.base/java.util.concurrent.ConcurrentHashMap.putIfAbsent(ConcurrentHashMap.java:1541)
[info]          at java.base/java.lang.ClassLoader.getClassLoadingLock(ClassLoader.java:668)
[info]          at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:591)
[info]          at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579)
[info]          at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
[info]          at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
```

The solution is to expand the stack size of a thread in the test from 32KB to 256KB.
Currently, the stack size is specified as 32KB but the actual stack size can be greater than 32KB.
According to the code of Hotspot, the minimum stack size is prefer to the specified size.

Java 8: https://hg.openjdk.java.net/jdk8u/jdk8u/hotspot/file/c92ba514724d/src/os/linux/vm/os_linux.cpp#l900
Java 11: https://hg.openjdk.java.net/jdk-updates/jdk11u/file/73edf743a93a/src/hotspot/os/posix/os_posix.cpp#l1555

For Linux on x86_64, the minimum stack size seems to be 224KB and 136KB for Java 8 and Java 11 respectively. So, the actual stack size should be 224KB rather than 32KB for Java 8 on x86_64/Linux.
As the test passes for Java 8 but doesn't for Java 11, 224KB is enough while 136KB is not.
So I think specifing 256KB is reasonable for the new stack size.

### Why are the changes needed?

To pass the test for Java 11.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Following command with Java 11.
```
build/sbt -Pyarn clean package "testOnly org.apache.spark.deploy.yarn.LocalityPlacementStrategySuite"
```

Closes #29943 from sarutak/fix-stack-size.

Authored-by: Kousuke Saruta <sarutak@oss.nttdata.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
### What changes were proposed in this pull request?

Adding a method to get the checkpoint directory from the PySpark context to match the Scala API

### Why are the changes needed?

To make the Scala and Python APIs consistent and remove the need to use the JavaObject

### Does this PR introduce _any_ user-facing change?

Yes, there is a new method which makes it easier to get the checkpoint directory directly rather than using the JavaObject

#### Previous behaviour:
```python
>>> spark.sparkContext.setCheckpointDir('/tmp/spark/checkpoint/')
>>> sc._jsc.sc().getCheckpointDir().get()
'file:/tmp/spark/checkpoint/63f7b67c-e5dc-4d11-a70c-33554a71717a'
```
This method returns a confusing Scala error if it has not been set
```python
>>> sc._jsc.sc().getCheckpointDir().get()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/paul/Desktop/spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/home/paul/Desktop/spark/python/pyspark/sql/utils.py", line 111, in deco
    return f(*a, **kw)
  File "/home/paul/Desktop/spark/python/lib/py4j-0.10.9-src.zip/py4j/protocol.py", line 328, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o25.get.
: java.util.NoSuchElementException: None.get
        at scala.None$.get(Option.scala:529)
        at scala.None$.get(Option.scala:527)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
        at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
        at py4j.Gateway.invoke(Gateway.java:282)
        at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
        at py4j.commands.CallCommand.execute(CallCommand.java:79)
        at py4j.GatewayConnection.run(GatewayConnection.java:238)
        at java.lang.Thread.run(Thread.java:748)

```

#### New method:
```python
>>> spark.sparkContext.setCheckpointDir('/tmp/spark/checkpoint/')
>>> spark.sparkContext.getCheckpointDir()
'file:/tmp/spark/checkpoint/b38aca2e-8ace-44fc-a4c4-f4e36c2da2a7'
```

``getCheckpointDir()`` returns ``None`` if it has not been set
```python
>>> print(spark.sparkContext.getCheckpointDir())
None
```

### How was this patch tested?

Added to existing unit tests. But I'm not sure how to add a test for the case where ``getCheckpointDir()`` should return ``None`` since the existing checkpoint tests set the checkpoint directory in the ``setUp`` method before any tests are run as far as I can tell.

Closes #29918 from reidy-p/SPARK-33017.

Authored-by: reidy-p <paul_reidy@outlook.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
### What changes were proposed in this pull request?

Add SparkR wrapper for `o.a.s.ml.functions.vector_to_array`

### Why are the changes needed?

- Currently ML vectors, including predictions, are almost inaccessible to R users. That's is a serious loss of functionality.
- Feature parity.

### Does this PR introduce _any_ user-facing change?

Yes, new R function is added.

### How was this patch tested?

- New unit tests.
- Manual verification.

Closes #29917 from zero323/SPARK-33040.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
### What changes were proposed in this pull request?

- Reorder choices of `dtype` to match Scala defaults.
- Add example to ml_functions.

### Why are the changes needed?

As requested:

- #29917 (review)
- #29917 (review)

### Does this PR introduce _any_ user-facing change?

No (changes to newly added component).

### How was this patch tested?

Existing tests.

Closes #29944 from zero323/SPARK-33040-FOLLOW-UP.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
…ql.optimizer.maxIterations take effect at runtime

### What changes were proposed in this pull request?

Add a test case to ensure changes to `spark.sql.optimizer.maxIterations` take effect at runtime.

### Why are the changes needed?

Currently, there is only one related test case: https://github.com/apache/spark/blob/master/sql/core/src/test/scala/org/apache/spark/sql/internal/SQLConfSuite.scala#L156

However, this test case only checks the value of the conf can be changed at runtime. It does not check the updated value is actually used by the Optimizer.

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

unit test

Closes #29919 from yuningzh-db/add_optimizer_test.

Authored-by: Yuning Zhang <yuning.zhang@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
### What changes were proposed in this pull request?

Some expression's data type not a static value. It needs to be constructed a new object when calling `dataType` function. E.g.: `CaseWhen`.
We should avoid constructing dataType multiple times because it may be used many times. E.g.: [`HyperLogLogPlusPlus.update`](https://github.com/apache/spark/blob/10edeafc69250afef8c71ed7b3c77992f67aa4ff/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregate/HyperLogLogPlusPlus.scala#L122).

### Why are the changes needed?

Improve query performance. for example:
```scala
spark.range(100000000L).selectExpr("approx_count_distinct(case when id % 400 > 20 then id else 0 end)").show
```

Profiling result:
```
-- Execution profile ---
Total samples       : 18365

Frame buffer usage  : 2.6688%

--- 58443254327 ns (31.82%), 5844 samples
  [ 0] GenericTaskQueueSet<OverflowTaskQueue<StarTask, (MemoryType)1, 131072u>, (MemoryType)1>::steal_best_of_2(unsigned int, int*, StarTask&)
  [ 1] StealTask::do_it(GCTaskManager*, unsigned int)
  [ 2] GCTaskThread::run()
  [ 3] java_start(Thread*)
  [ 4] start_thread

--- 6140668667 ns (3.34%), 614 samples
  [ 0] GenericTaskQueueSet<OverflowTaskQueue<StarTask, (MemoryType)1, 131072u>, (MemoryType)1>::peek()
  [ 1] ParallelTaskTerminator::offer_termination(TerminatorTerminator*)
  [ 2] StealTask::do_it(GCTaskManager*, unsigned int)
  [ 3] GCTaskThread::run()
  [ 4] java_start(Thread*)
  [ 5] start_thread

--- 5679994036 ns (3.09%), 568 samples
  [ 0] scala.collection.generic.Growable.$plus$plus$eq
  [ 1] scala.collection.generic.Growable.$plus$plus$eq$
  [ 2] scala.collection.mutable.ListBuffer.$plus$plus$eq
  [ 3] scala.collection.mutable.ListBuffer.$plus$plus$eq
  [ 4] scala.collection.generic.GenericTraversableTemplate.$anonfun$flatten$1
  [ 5] scala.collection.generic.GenericTraversableTemplate$$Lambda$107.411506101.apply
  [ 6] scala.collection.immutable.List.foreach
  [ 7] scala.collection.generic.GenericTraversableTemplate.flatten
  [ 8] scala.collection.generic.GenericTraversableTemplate.flatten$
  [ 9] scala.collection.AbstractTraversable.flatten
  [10] org.apache.spark.internal.config.ConfigEntry.readString
  [11] org.apache.spark.internal.config.ConfigEntryWithDefault.readFrom
  [12] org.apache.spark.sql.internal.SQLConf.getConf
  [13] org.apache.spark.sql.internal.SQLConf.caseSensitiveAnalysis
  [14] org.apache.spark.sql.types.DataType.sameType
  [15] org.apache.spark.sql.catalyst.analysis.TypeCoercion$.$anonfun$haveSameType$1
  [16] org.apache.spark.sql.catalyst.analysis.TypeCoercion$.$anonfun$haveSameType$1$adapted
  [17] org.apache.spark.sql.catalyst.analysis.TypeCoercion$$$Lambda$1527.1975399904.apply
  [18] scala.collection.IndexedSeqOptimized.prefixLengthImpl
  [19] scala.collection.IndexedSeqOptimized.forall
  [20] scala.collection.IndexedSeqOptimized.forall$
  [21] scala.collection.mutable.ArrayBuffer.forall
  [22] org.apache.spark.sql.catalyst.analysis.TypeCoercion$.haveSameType
  [23] org.apache.spark.sql.catalyst.expressions.ComplexTypeMergingExpression.dataTypeCheck
  [24] org.apache.spark.sql.catalyst.expressions.ComplexTypeMergingExpression.dataTypeCheck$
  [25] org.apache.spark.sql.catalyst.expressions.CaseWhen.dataTypeCheck
  [26] org.apache.spark.sql.catalyst.expressions.ComplexTypeMergingExpression.dataType
  [27] org.apache.spark.sql.catalyst.expressions.ComplexTypeMergingExpression.dataType$
  [28] org.apache.spark.sql.catalyst.expressions.CaseWhen.dataType
  [29] org.apache.spark.sql.catalyst.expressions.aggregate.HyperLogLogPlusPlus.update
  [30] org.apache.spark.sql.execution.aggregate.AggregationIterator$$anonfun$1.$anonfun$applyOrElse$2
  [31] org.apache.spark.sql.execution.aggregate.AggregationIterator$$anonfun$1.$anonfun$applyOrElse$2$adapted
  [32] org.apache.spark.sql.execution.aggregate.AggregationIterator$$anonfun$1$$Lambda$1534.1383512673.apply
  [33] org.apache.spark.sql.execution.aggregate.AggregationIterator.$anonfun$generateProcessRow$7
  [34] org.apache.spark.sql.execution.aggregate.AggregationIterator.$anonfun$generateProcessRow$7$adapted
  [35] org.apache.spark.sql.execution.aggregate.AggregationIterator$$Lambda$1555.725788712.apply
```

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manual test and benchmark test:

Benchmark code | Before this PR(Milliseconds) | After this PR(Milliseconds)
--- | --- | ---
spark.range(100000000L).selectExpr("approx_count_distinct(case   when id % 400 > 20 then id else 0 end)").collect() | 56462 | 3794

Closes #29790 from wangyum/SPARK-32914.

Authored-by: Yuming Wang <yumwang@ebay.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
…confs

### What changes were proposed in this pull request?
Provide error handling when creating kubernetes volumes. Right now they keys are expected to be there and if not it fails with a `key not found` error, but not knowing why do you need that `key`.

Also I renamed some tests that didn't indicate the kind of kubernetes volume

### Why are the changes needed?

Easier for the users to understand why `spark-submit` command is failing if not providing they right kubernetes volumes properties.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
It was tested with the current tests plus added one more.

[Jira ticket](https://issues.apache.org/jira/browse/SPARK-33063)

Closes #29941 from Gschiavon/SPARK-33063-provide-error-handling-k8s-volumes.

Authored-by: gschiavon <germanschiavon@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
…wo plans are the same

### What changes were proposed in this pull request?
This PR combines the current plan and the initial plan in the AQE query plan string when the two plans are the same. It also removes the `== Current Plan ==` and `== Initial Plan ==` headers:

Before
```scala
AdaptiveSparkPlan isFinalPlan=false
+- == Current Plan ==
   SortMergeJoin [key#13], [a#23], Inner
   :- Sort [key#13 ASC NULLS FIRST], false, 0
   :  +- Exchange hashpartitioning(key#13, 5), true, [id=#94]
            ...
+- == Initial Plan ==
   SortMergeJoin [key#13], [a#23], Inner
   :- Sort [key#13 ASC NULLS FIRST], false, 0
   :  +- Exchange hashpartitioning(key#13, 5), true, [id=#94]
            ...
```
After
```scala
AdaptiveSparkPlan isFinalPlan=false
+- SortMergeJoin [key#13], [a#23], Inner
   :- Sort [key#13 ASC NULLS FIRST], false, 0
   :  +- Exchange hashpartitioning(key#13, 5), true, [id=#94]
            ...
```
For SQL `EXPLAIN` output:
Before
```scala
AdaptiveSparkPlan (8)
+- == Current Plan ==
   Sort (7)
   +- Exchange (6)
      ...
+- == Initial Plan ==
   Sort (7)
   +- Exchange (6)
      ...
```
After
```scala
AdaptiveSparkPlan (8)
+- Sort (7)
   +- Exchange (6)
      ...
```

### Why are the changes needed?
To simplify the AQE plan string by removing the redundant plan information.

### Does this PR introduce _any_ user-facing change?
Yes.

### How was this patch tested?
Modified the existing unit test.

Closes #29915 from allisonwang-db/aqe-explain.

Authored-by: allisonwang-db <66282705+allisonwang-db@users.noreply.github.com>
Signed-off-by: Xiao Li <gatorsmile@gmail.com>
… (Hive 1.2.1)

### What changes were proposed in this pull request?

As of today,
- SPARK-30034 Apache Spark 3.0.0 switched its default Hive execution engine from Hive 1.2 to Hive 2.3. This removes the direct dependency to the forked Hive 1.2.1 in maven repository.
- SPARK-32981 Apache Spark 3.1.0(`master` branch) removed Hive 1.2 related artifacts from Apache Spark binary distributions.

This PR(SPARK-20202) aims to remove the following usage of unofficial Apache Hive fork completely from Apache Spark master for Apache Spark 3.1.0.
```
<hive.group>org.spark-project.hive</hive.group>
<hive.version>1.2.1.spark2</hive.version>
```

For the forked Hive 1.2.1.spark2 users, Apache Spark 2.4(LTS) and 3.0 (~ 2021.12) will provide it.

### Why are the changes needed?

- First, Apache Spark community should not use the unofficial forked release of another Apache project.
- Second, Apache Hive 1.2.1 was released at 2015-06-26 and the forked Hive `1.2.1.spark2` exposed many unfixable bugs in Apache because the forked `1.2.1.spark2` is not maintained at all. Apache Hive 2.3.0 was released at 2017-07-19 and it has been used with less number of bugs compared with `1.2.1.spark2`. Many bugs still exist in `hive-1.2` profile and new Apache Spark unit tests are added with `HiveUtils.isHive23` condition so far.

### Does this PR introduce _any_ user-facing change?

No. This is a dev-only change. PRBuilder will not accept `[test-hive1.2]` on master and `branch-3.1`.

### How was this patch tested?

1. SBT/Hadoop 3.2/Hive 2.3 (https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/129366)
2. SBT/Hadoop 2.7/Hive 2.3 (https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/129382)
3. SBT/Hadoop 3.2/Hive 1.2 (This has not been supported already due to Hive 1.2 doesn't work with Hadoop 3.2.)
4. SBT/Hadoop 2.7/Hive 1.2 (https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/129383, This is rejected)

Closes #29936 from dongjoon-hyun/SPARK-REMOVE-HIVE1.

Authored-by: Dongjoon Hyun <dhyun@apple.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
…e found

### What changes were proposed in this pull request?

This PR proposes to skip test reporting ("Report test results") if there are no JUnit XML files are found.

Currently, we're running and skipping the tests dynamically. For example,
- if there are only changes in SparkR at the underlying commit, it only runs the SparkR tests, and skip the other tests and generate JUnit XML files for SparkR test cases.
- if there are only changes in `docs` at the underlying commit, the build skips all tests except linters and do not generate any JUnit XML files.

When test reporting ("Report test results") job is triggered after the main build ("Build and test
") is finished, and there are no JUnit XML files found, it reports the case as a failure. See https://github.com/apache/spark/runs/1196184007 as an example.

This PR works around it by simply skipping the testing report when there are no JUnit XML files are found.
Please see #29906 (comment) for more details.

### Why are the changes needed?

To avoid false alarm for test results.

### Does this PR introduce _any_ user-facing change?

No, dev-only.

### How was this patch tested?

Manually tested in my fork.

Positive case:

https://github.com/HyukjinKwon/spark/runs/1208624679?check_suite_focus=true
https://github.com/HyukjinKwon/spark/actions/runs/288996327

Negative case:

https://github.com/HyukjinKwon/spark/runs/1208229838?check_suite_focus=true
https://github.com/HyukjinKwon/spark/actions/runs/289000058

Closes #29946 from HyukjinKwon/test-junit-files.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
…g tests

### What changes were proposed in this pull request?
Add checks for the cases when JDBC v2 Table Catalog commands fail.

### Why are the changes needed?
To improve test coverage.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
By running `JDBCTableCatalogSuite`.

Closes #29945 from MaxGekk/jdbcv2-negative-tests.

Lead-authored-by: Max Gekk <max.gekk@gmail.com>
Co-authored-by: Hyukjin Kwon <gurwls223@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
@GulajavaMinistudio GulajavaMinistudio merged commit 27ee3a7 into GulajavaMinistudio:master Oct 6, 2020
GulajavaMinistudio pushed a commit that referenced this pull request Feb 3, 2025
This is a trivial change to replace the loop index from `int` to `long`. Surprisingly, microbenchmark shows more than double performance uplift.

Analysis
--------
The hot loop of `arrayEquals` method is simplifed as below. Loop index `i` is defined as `int`, it's compared with `length`, which is a `long`, to determine if the loop should end.
```
public static boolean arrayEquals(
    Object leftBase, long leftOffset, Object rightBase, long rightOffset, final long length) {
  ......
  int i = 0;
  while (i <= length - 8) {
    if (Platform.getLong(leftBase, leftOffset + i) !=
        Platform.getLong(rightBase, rightOffset + i)) {
          return false;
    }
    i += 8;
  }
  ......
}
```

Strictly speaking, there's a code bug here. If `length` is greater than 2^31 + 8, this loop will never end because `i` as a 32 bit integer is at most 2^31 - 1. But compiler must consider this behaviour as intentional and generate code strictly match the logic. It prevents compiler from generating optimal code.

Defining loop index `i` as `long` corrects this issue. Besides more accurate code logic, JIT is able to optimize this code much more aggressively. From microbenchmark, this trivial change improves performance significantly on both Arm and x86 platforms.

Benchmark
---------
Source code:
https://gist.github.com/cyb70289/258e261f388e22f47e4d961431786d1a

Result on Arm Neoverse N2:
```
Benchmark                             Mode  Cnt    Score   Error  Units
ArrayEqualsBenchmark.arrayEqualsInt   avgt   10  674.313 ± 0.213  ns/op
ArrayEqualsBenchmark.arrayEqualsLong  avgt   10  313.563 ± 2.338  ns/op
```

Result on Intel Cascake Lake:
```
Benchmark                             Mode  Cnt     Score   Error  Units
ArrayEqualsBenchmark.arrayEqualsInt   avgt   10  1130.695 ± 0.168  ns/op
ArrayEqualsBenchmark.arrayEqualsLong  avgt   10   461.979 ± 0.097  ns/op
```

Deep dive
---------
Dive deep to the machine code level, we can see why the big gap. Listed below are arm64 assembly generated by Openjdk-17 C2 compiler.

For `int i`, the machine code is similar to source code, no deep optimization. Safepoint polling is expensive in this short loop.
```
// jit c2 machine code snippet
  0x0000ffff81ba8904:   mov        w15, wzr              // int i = 0
  0x0000ffff81ba8908:   nop
  0x0000ffff81ba890c:   nop
loop:
  0x0000ffff81ba8910:   ldr        x10, [x13, w15, sxtw] // Platform.getLong(leftBase, leftOffset + i)
  0x0000ffff81ba8914:   ldr        x14, [x12, w15, sxtw] // Platform.getLong(rightBase, rightOffset + i)
  0x0000ffff81ba8918:   cmp        x10, x14
  0x0000ffff81ba891c:   b.ne       0x0000ffff81ba899c    // return false if not equal
  0x0000ffff81ba8920:   ldr        x14, [x28, #848]      // x14 -> safepoint
  0x0000ffff81ba8924:   add        w15, w15, #0x8        // i += 8
  0x0000ffff81ba8928:   ldr        wzr, [x14]            // safepoint polling
  0x0000ffff81ba892c:   sxtw       x10, w15              // extend i to long
  0x0000ffff81ba8930:   cmp        x10, x11
  0x0000ffff81ba8934:   b.le       0x0000ffff81ba8910    // if (i <= length - 8) goto loop
```

For `long i`, JIT is able to do much more aggressive optimization. E.g, below code snippet unrolls the loop by four.
```
// jit c2 machine code snippet
unrolled_loop:
  0x0000ffff91de6fe0:   sxtw       x10, w7
  0x0000ffff91de6fe4:   add        x23, x22, x10
  0x0000ffff91de6fe8:   add        x24, x21, x10
  0x0000ffff91de6fec:   ldr        x13, [x23]          // unroll-1
  0x0000ffff91de6ff0:   ldr        x14, [x24]
  0x0000ffff91de6ff4:   cmp        x13, x14
  0x0000ffff91de6ff8:   b.ne       0x0000ffff91de70a8
  0x0000ffff91de6ffc:   ldr        x13, [x23, #8]      // unroll-2
  0x0000ffff91de7000:   ldr        x14, [x24, #8]
  0x0000ffff91de7004:   cmp        x13, x14
  0x0000ffff91de7008:   b.ne       0x0000ffff91de70b4
  0x0000ffff91de700c:   ldr        x13, [x23, #16]     // unroll-3
  0x0000ffff91de7010:   ldr        x14, [x24, #16]
  0x0000ffff91de7014:   cmp        x13, x14
  0x0000ffff91de7018:   b.ne       0x0000ffff91de70a4
  0x0000ffff91de701c:   ldr        x13, [x23, #24]     // unroll-4
  0x0000ffff91de7020:   ldr        x14, [x24, #24]
  0x0000ffff91de7024:   cmp        x13, x14
  0x0000ffff91de7028:   b.ne       0x0000ffff91de70b0
  0x0000ffff91de702c:   add        w7, w7, #0x20
  0x0000ffff91de7030:   cmp        w7, w11
  0x0000ffff91de7034:   b.lt       0x0000ffff91de6fe0
```

### What changes were proposed in this pull request?

A trivial change to replace loop index `i` of method `arrayEquals` from `int` to `long`.

### Why are the changes needed?

To improve performance and fix a possible bug.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Existing unit tests.

### Was this patch authored or co-authored using generative AI tooling?

No.

Closes apache#49568 from cyb70289/arrayEquals.

Authored-by: Yibo Cai <cyb70289@gmail.com>
Signed-off-by: Sean Owen <srowen@gmail.com>
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