[SPARK-1646] Micro-optimisation of ALS

This change replaces some Scala `for` and `foreach` constructs with `while` constructs.  There may be a slight performance gain on the order of 1-2% when training an ALS model.

I trained an ALS model on the Movielens 10M-rating dataset repeatedly both with and without these changes.  All 7 runs in both columns were done in a Scala `for` loop like this:

    for (iter <- 0 to 10) {
      val before = System.currentTimeMillis()
      val model = ALS.train(rats, 20, 10)
      val after = System.currentTimeMillis()
      println("%d ms".format(after-before))
      println("rmse %g".format(computeRmse(model, rats, numRatings)))
    }

The timings were done on a multiuser machine, and I stopped one set of timings after 7 had been completed.  It would be nice if somebody with dedicated hardware could confirm my timings.

    After           Before
    121980 ms       122041 ms
    117069 ms       117127 ms
    115332 ms       117523 ms
    115381 ms       117402 ms
    114635 ms       116550 ms
    114140 ms       114076 ms
    112993 ms       117200 ms

Ratios are about 1.0005, 1.0005, 1.019, 1.0175, 1.01671, 0.99944, and 1.03723.  I therefore suspect these changes make for a slight performance gain on the order of 1-2%.

Author: Tor Myklebust <tmyklebu@gmail.com>

Closes #568 from tmyklebu/alsopt and squashes the following commits:

5ded80f [Tor Myklebust] Fix style.
79595ff [Tor Myklebust] Fix style error.
4ef0313 [Tor Myklebust] Merge branch 'master' of github.com:apache/spark into alsopt
114fb74 [Tor Myklebust] Turn some 'for' loops into 'while' loops.
dcf583a [Tor Myklebust] Remove the partitioner member variable; instead, thread that needle everywhere it needs to go.
23d6f91 [Tor Myklebust] Stop making the partitioner configurable.
495784f [Tor Myklebust] Merge branch 'master' of https://github.com/apache/spark
674933a [Tor Myklebust] Fix style.
40edc23 [Tor Myklebust] Fix missing space.
f841345 [Tor Myklebust] Fix daft bug creating 'pairs', also for -> foreach.
5ec9e6c [Tor Myklebust] Clean a couple of things up using 'map'.
36a0f43 [Tor Myklebust] Make the partitioner private.
d872b09 [Tor Myklebust] Add negative id ALS test.
df27697 [Tor Myklebust] Support custom partitioners.  Currently we use the same partitioner for users and products.
c90b6d8 [Tor Myklebust] Scramble user and product ids before bucketing.
c774d7d [Tor Myklebust] Make the partitioner a member variable and use it instead of modding directly.
Args for worker rather than master

Args for worker rather than master

Author: Chen Chao <crazyjvm@gmail.com>

Closes #587 from CrazyJvm/patch-6 and squashes the following commits:

b54b89f [Chen Chao] Args for worker rather than master
Handle the vals that never used

In XORShiftRandom.scala, use val "million" instead of constant "1e6.toInt".
Delete vals that never used in other files.

Author: WangTao <barneystinson@aliyun.com>

Closes #565 from WangTaoTheTonic/master and squashes the following commits:

17cacfc [WangTao] Handle the unused assignment, method parameters and symbol inspected by Intellij IDEA
37b4090 [WangTao] Handle the vals that never used
SPARK-1004.  PySpark on YARN

This reopens https://github.com/apache/incubator-spark/pull/640 against the new repo

Author: Sandy Ryza <sandy@cloudera.com>

Closes #30 from sryza/sandy-spark-1004 and squashes the following commits:

89889d4 [Sandy Ryza] Move unzipping py4j to the generate-resources phase so that it gets included in the jar the first time
5165a02 [Sandy Ryza] Fix docs
fd0df79 [Sandy Ryza] PySpark on YARN
Fix SPARK-1629: Spark should inline use of commons-lang `SystemUtils.IS_...

...OS_WINDOWS`

Author: witgo <witgo@qq.com>

Closes #569 from witgo/SPARK-1629 and squashes the following commits:

31520eb [witgo] Merge branch 'master' of https://github.com/apache/spark into SPARK-1629
fcaafd7 [witgo] merge mastet
49e248e [witgo] Fix SPARK-1629: Spark should inline use of commons-lang `SystemUtils.IS_OS_WINDOWS`
SPARK-1691: Support quoted arguments inside of spark-submit.

This is a fairly straightforward fix. The bug was reported by @vanzin and the fix was proposed by @deanwampler and myself. Please take a look!

Author: Patrick Wendell <pwendell@gmail.com>

Closes #609 from pwendell/quotes and squashes the following commits:

8bed767 [Patrick Wendell] SPARK-1691: Support quoted arguments inside of spark-submit.
[SQL] SPARK-1661 - Fix regex_serde test

The JIRA in question is actually reporting a bug with Shark, but I wanted to make sure Spark SQL did not have similar problems.  This fixes a bug in our parsing code that was preventing the test from executing, but it looks like the RegexSerDe is working in Spark SQL.

Author: Michael Armbrust <michael@databricks.com>

Closes #595 from marmbrus/fixRegexSerdeTest and squashes the following commits:

a4dc612 [Michael Armbrust] Add files created by hive to gitignore.
efa6402 [Michael Armbrust] Fix Hive serde_regex test.
fix the spelling mistake

Author: wangfei <wangfei_hello@126.com>

Closes #614 from scwf/pxcw and squashes the following commits:

d1016ba [wangfei] fix spelling mistake
 SPARK-1659: improvements spark-submit usage

Author: witgo <witgo@qq.com>

Closes #581 from witgo/SPARK-1659 and squashes the following commits:

0b2cf98 [witgo] Delete spark-submit obsolete usage: "--arg ARG"
Add tests for FileLogger, EventLoggingListener, and ReplayListenerBus

Modifications to Spark core are limited to exposing functionality to test files + minor style fixes.
(728 / 769 lines are from tests)

Author: Andrew Or <andrewor14@gmail.com>

Closes #591 from andrewor14/event-log-tests and squashes the following commits:

2883837 [Andrew Or] Merge branch 'master' of github.com:apache/spark into event-log-tests
c3afcea [Andrew Or] Compromise
2d5daf8 [Andrew Or] Use temp directory provided by the OS rather than /tmp
2b52151 [Andrew Or] Remove unnecessary file delete + add a comment
62010fd [Andrew Or] More cleanup (renaming variables, updating comments etc)
ad2beff [Andrew Or] Clean up EventLoggingListenerSuite + modify a few comments
862e752 [Andrew Or] Merge branch 'master' of github.com:apache/spark into event-log-tests
e0ba2f8 [Andrew Or] Fix test failures caused by race condition in processing/mutating events
b990453 [Andrew Or] ReplayListenerBus suite - tests do not all pass yet
ab66a84 [Andrew Or] Tests for FileLogger + delete file after tests
187bb25 [Andrew Or] Formatting and renaming variables
769336f [Andrew Or] Merge branch 'master' of github.com:apache/spark into event-log-tests
5d38ffe [Andrew Or] Clean up EventLoggingListenerSuite + add comments
e12f4b1 [Andrew Or] Preliminary tests for EventLoggingListener (need major cleanup)
SPARK-1695: java8-tests compiler error: package com.google.common.co...

...llections does not exist

Author: witgo <witgo@qq.com>

Closes #611 from witgo/SPARK-1695 and squashes the following commits:

d77a887 [witgo] Fix SPARK-1695: java8-tests compiler error: package com.google.common.collections does not exist
delete no use var

Author: wangfei <wangfei_hello@126.com>

Closes #613 from scwf/masterIndex and squashes the following commits:

1463056 [wangfei] delete no use var: masterIndex
SPARK-1492. Update Spark YARN docs to use spark-submit

Author: Sandy Ryza <sandy@cloudera.com>

Closes #601 from sryza/sandy-spark-1492 and squashes the following commits:

5df1634 [Sandy Ryza] Address additional comments from Patrick.
be46d1f [Sandy Ryza] Address feedback from Marcelo and Patrick
867a3ea [Sandy Ryza] SPARK-1492. Update Spark YARN docs to use spark-submit
SPARK-1700: Close socket file descriptors on task completion

This will ensure that sockets do not build up over the course of a job, and that cancellation successfully cleans up sockets.

Tested in standalone mode. More file descriptors spawn than expected (around 1000ish rather than the expected 8ish) but they do not pile up between runs, or as high as before (where they went up to around 5k).

Author: Aaron Davidson <aaron@databricks.com>

Closes #623 from aarondav/pyspark2 and squashes the following commits:

0ca13bb [Aaron Davidson] SPARK-1700: Close socket file descriptors on task completion
Update SchemaRDD.scala

Modify spelling errors

Author: ArcherShao <ArcherShao@users.noreply.github.com>

Closes #619 from ArcherShao/patch-1 and squashes the following commits:

2957195 [ArcherShao] Update SchemaRDD.scala
[WIP] SPARK-1676: Cache Hadoop UGIs by default to prevent FileSystem leak

Move the doAs in Executor higher up so that we only have 1 ugi and aren't leaking filesystems.
Fix spark on yarn to work when the cluster is running as user "yarn" but the clients are launched as the user and want to read/write to hdfs as the user.

Note this hasn't been fully tested yet.  Need to test in standalone mode.

Putting this up for people to look at and possibly test.  I don't have access to a mesos cluster.

This is alternative to https://github.com/apache/spark/pull/607

Author: Thomas Graves <tgraves@apache.org>

Closes #621 from tgravescs/SPARK-1676 and squashes the following commits:

244d55a [Thomas Graves] fix line length
44163d4 [Thomas Graves] Rework
9398853 [Thomas Graves] change to have doAs in executor higher up.
SPARK-1663. Corrections for several compile errors in streaming code examples, and updates to follow API changes

I gave the Streaming code examples, both Scala and Java, a test run today. I turned up a number of small errors, mostly compile errors in the Java examples. There were a few typos in the Scala too.

I also took the liberty of adding things like imports, since in several cases they are not obvious. Feel free to push back on some changes.

There's one thing I haven't quite addressed in the changes. `JavaPairDStream` uses the Java API version of `Function2` in almost all cases, as `JFunction2`. However it uses `scala.Function2` in:

```
  def reduceByKeyAndWindow(reduceFunc: Function2[V, V, V], windowDuration: Duration)
  :JavaPairDStream[K, V] = {
    dstream.reduceByKeyAndWindow(reduceFunc, windowDuration)
  }
```

Is that a typo?

Also, in Scala, I could not get this to compile:
```
val windowedWordCounts = pairs.reduceByKeyAndWindow(_ + _, Seconds(30), Seconds(10))
error: missing parameter type for expanded function ((x$1, x$2) => x$1.$plus(x$2))
```

You can see my fix below but am I missing something?

Otherwise I can say these all worked for me!

Author: Sean Owen <sowen@cloudera.com>

Closes #589 from srowen/SPARK-1663 and squashes the following commits:

65a906b [Sean Owen] Corrections for several compile errors in streaming code examples, and updates to follow API changes
[Bugfix] Tachyon file cleanup logical error

Should lookup `shutdownDeleteTachyonPaths` instead of `shutdownDeletePaths`. Together with a minor style clean up: `find {...}.isDefined` to `exists {...}`.

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #575 from liancheng/tachyonFix and squashes the following commits:

deb8f31 [Cheng Lian] Fixed logical error in when cleanup Tachyon files and minor style cleanup
SPARK-1689 AppClient should indicate app is dead() when removed

Previously, we indicated disconnected(), which keeps the application in a limbo state where it has no executors but thinks it will get them soon.

This is a bug fix that hopefully can be included in 1.0.

Author: Aaron Davidson <aaron@databricks.com>

Closes #605 from aarondav/appremoved and squashes the following commits:

bea02a2 [Aaron Davidson] SPARK-1689 AppClient should indicate app is dead() when removed
EC2 configurable workers

Added option to configure number of worker instances and to set SPARK_MASTER_OPTS

Depends on: https://github.com/mesos/spark-ec2/pull/46

Author: Allan Douglas R. de Oliveira <allan@chaordicsystems.com>

Closes #612 from douglaz/ec2_configurable_workers and squashes the following commits:

d6c5d65 [Allan Douglas R. de Oliveira] Added master opts parameter
6c34671 [Allan Douglas R. de Oliveira] Use number of worker instances as string on template
ba528b9 [Allan Douglas R. de Oliveira] Added SPARK_WORKER_INSTANCES parameter