Remove use of spark.worker.instances

spark.worker.instances was added as part of this commit: https://github.com/apache/spark/commit/1617816090e7b20124a512a43860a21232ebf511

My understanding is that SPARK_WORKER_INSTANCES is supported for backwards compatibility,
but spark.worker.instances is never used (SparkSubmit.scala sets spark.executor.instances) so should
not have been added.

@sryza @pwendell @tgravescs LMK if I'm understanding this correctly

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #1214 from kayousterhout/yarn_config and squashes the following commits:

3d7c491 [Kay Ousterhout] Remove use of spark.worker.instances
[SPARK-2295] [SQL] Make JavaBeans nullability stricter.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #1235 from ueshin/issues/SPARK-2295 and squashes the following commits:

201c508 [Takuya UESHIN] Make JavaBeans nullability stricter.
[SPARK-2286][UI] Report exception/errors for failed tasks that are not ExceptionFailure

Also added inline doc for each TaskEndReason.

Author: Reynold Xin <rxin@apache.org>

Closes #1225 from rxin/SPARK-2286 and squashes the following commits:

6a7959d [Reynold Xin] Fix unit test failure.
cf9d5eb [Reynold Xin] Merge branch 'master' into SPARK-2286
a61fae1 [Reynold Xin] Move to line above ...
38c7391 [Reynold Xin] [SPARK-2286][UI] Report exception/errors for failed tasks that are not ExceptionFailure.
Fixing AWS instance type information based upon current EC2 data

Fixed a problem in previous file in which some information regarding AWS instance types were wrong. Such information was updated base upon current AWS EC2 data.

Author: Zichuan Ye <jerry@tangentds.com>

Closes #1156 from jerry86/master and squashes the following commits:

ff36e95 [Zichuan Ye] Fixing AWS instance type information based upon current EC2 data
Strip '@' symbols when merging pull requests.

Currently all of the commits with 'X' in them cause person X to
receive e-mails every time someone makes a public fork of Spark.

marmbrus who requested this.

Author: Patrick Wendell <pwendell@gmail.com>

Closes #1239 from pwendell/strip and squashes the following commits:

22e5a97 [Patrick Wendell] Strip '@' symbols when merging pull requests.
[SQL]Extract the joinkeys from join condition

Extract the join keys from equality conditions, that can be evaluated using equi-join.

Author: Cheng Hao <hao.cheng@intel.com>

Closes #1190 from chenghao-intel/extract_join_keys and squashes the following commits:

4a1060a [Cheng Hao] Fix some of the small issues
ceb4924 [Cheng Hao] Remove the redundant pattern of join keys extraction
cec34e8 [Cheng Hao] Update the code style issues
dcc4584 [Cheng Hao] Extract the joinkeys from join condition
Removed throwable field from FetchFailedException and added MetadataFetchFailedException

FetchFailedException used to have a Throwable field, but in reality we never propagate any of the throwable/exceptions back to the driver because Executor explicitly looks for FetchFailedException and then sends FetchFailed as the TaskEndReason.

This pull request removes the throwable and adds a MetadataFetchFailedException that extends FetchFailedException (so now MapOutputTracker throws MetadataFetchFailedException instead).

Author: Reynold Xin <rxin@apache.org>

Closes #1227 from rxin/metadataFetchException and squashes the following commits:

5cb1e0a [Reynold Xin] MetadataFetchFailedException extends FetchFailedException.
8861ee2 [Reynold Xin] Throw MetadataFetchFailedException in MapOutputTracker.
[SPARK-2297][UI] Make task attempt and speculation more explicit in UI.

New UI:

![screen shot 2014-06-26 at 1 43 52 pm](https://cloud.githubusercontent.com/assets/323388/3404643/82b9ddc6-fd73-11e3-96f9-f7592a7aee79.png)

Author: Reynold Xin <rxin@apache.org>

Closes #1236 from rxin/ui-task-attempt and squashes the following commits:

3b645dd [Reynold Xin] Expose attemptId in Stage.
c0474b1 [Reynold Xin] Beefed up unit test.
c404bdd [Reynold Xin] Fix ReplayListenerSuite.
f56be4b [Reynold Xin] Fixed JsonProtocolSuite.
e29e0f7 [Reynold Xin] Minor update.
5e4354a [Reynold Xin] [SPARK-2297][UI] Make task attempt and speculation more explicit in UI.
[SPARK-2251] fix concurrency issues in random sampler

The following code is very likely to throw an exception:

~~~
val rdd = sc.parallelize(0 until 111, 10).sample(false, 0.1)
rdd.zip(rdd).count()
~~~

because the same random number generator is used in compute partitions.

Author: Xiangrui Meng <meng@databricks.com>

Closes #1229 from mengxr/fix-sample and squashes the following commits:

f1ee3d7 [Xiangrui Meng] fix concurrency issues in random sampler
SPARK-2181:The keys for sorting the columns of Executor page in SparkUI are incorrect

Author: witgo <witgo@qq.com>

Closes #1135 from witgo/SPARK-2181 and squashes the following commits:

39dad90 [witgo] The keys for sorting the columns of Executor page in SparkUI are incorrect
[SPARK-2307] SparkUI - storage tab displays incorrect RDDs

The issue here is that the `StorageTab` listens for updates from the `StorageStatusListener`, but when a block is kicked out of the cache, `StorageStatusListener` removes it from its list. Thus, there is no way for the `StorageTab` to know whether a block has been dropped.

This issue was introduced in #1080, which was itself a bug fix. Here we revert that PR and offer a different fix for the original bug (SPARK-2144).

Author: Andrew Or <andrewor14@gmail.com>

Closes #1249 from andrewor14/storage-ui-fix and squashes the following commits:

af019ce [Andrew Or] Fix SPARK-2307
[SPARK-2259] Fix highly misleading docs on cluster / client deploy modes

The existing docs are highly misleading. For standalone mode, for example, it encourages the user to use standalone-cluster mode, which is not officially supported. The safeguards have been added in Spark submit itself to prevent bad documentation from leading users down the wrong path in the future.

This PR is prompted by countless headaches users of Spark have run into on the mailing list.

Author: Andrew Or <andrewor14@gmail.com>

Closes #1200 from andrewor14/submit-docs and squashes the following commits:

5ea2460 [Andrew Or] Rephrase cluster vs client explanation
c827f32 [Andrew Or] Clarify spark submit messages
9f7ed8f [Andrew Or] Clarify client vs cluster deploy mode + add safeguards
[SPARK-2003] Fix python SparkContext example

Author: Matthew Farrellee <matt@redhat.com>

Closes #1246 from mattf/SPARK-2003 and squashes the following commits:

b12e7ca [Matthew Farrellee] [SPARK-2003] Fix python SparkContext example
[SPARK-2233] make-distribution script should list the git hash in the RELEASE file

This patch adds the git revision hash (short version) to the RELEASE file. It uses git instead of simply checking for the existence of .git, so as to make sure that this is a functional repository.

Author: Guillaume Ballet <gballet@gmail.com>

Closes #1216 from gballet/master and squashes the following commits:

eabc50f [Guillaume Ballet] Refactored the script to take comments into account.
d93e5e8 [Guillaume Ballet] [SPARK 2233] make-distribution script now lists the git hash tag in the RELEASE file.
[SPARK-1394] Remove SIGCHLD handler in worker subprocess

It should not be the responsibility of the worker subprocess, which
does not intentionally fork, to try and cleanup child processes. Doing
so is complex and interferes with operations such as
platform.system().

If it is desirable to have tighter control over subprocesses, then
namespaces should be used and it should be the manager's resposibility
to handle cleanup.

Author: Matthew Farrellee <matt@redhat.com>

Closes #1247 from mattf/SPARK-1394 and squashes the following commits:

c36f308 [Matthew Farrellee] [SPARK-1394] Remove SIGCHLD handler in worker subprocess
Improve MapOutputTracker error logging.

Author: Reynold Xin <rxin@apache.org>

Closes #1258 from rxin/mapOutputTracker and squashes the following commits:

a7c95b6 [Reynold Xin] Improve MapOutputTracker error logging.
[SPARK-2320] Reduce exception/code block font size in web ui

Author: Reynold Xin <rxin@apache.org>

Closes #1261 from rxin/ui-pre-size and squashes the following commits:

7ab1a69 [Reynold Xin] [SPARK-2320] Reduce exception/code block font size in web ui
[SPARK-1683] Track task read metrics.

This commit adds a new metric in TaskMetrics to record
the input data size and displays this information in the UI.

An earlier version of this commit also added the read time,
which can be useful for diagnosing straggler problems,
but unfortunately that change introduced a significant performance
regression for jobs that don't do much computation. In order to
track read time, we'll need to do sampling.

The screenshots below show the UI with the new "Input" field,
which I added to the stage summary page, the executor summary page,
and the per-stage page.

![image](https://cloud.githubusercontent.com/assets/1108612/3167930/2627f92a-eb77-11e3-861c-98ea5bb7a1a2.png)

![image](https://cloud.githubusercontent.com/assets/1108612/3167936/475a889c-eb77-11e3-9706-f11c48751f17.png)

![image](https://cloud.githubusercontent.com/assets/1108612/3167948/80ebcf12-eb77-11e3-87ed-349fce6a770c.png)

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #962 from kayousterhout/read_metrics and squashes the following commits:

f13b67d [Kay Ousterhout] Correctly format input bytes on executor page
8b70cde [Kay Ousterhout] Added comment about potential inaccuracy of bytesRead
d1016e8 [Kay Ousterhout] Udated SparkListenerSuite test
8461492 [Kay Ousterhout] Miniscule style fix
ae04d99 [Kay Ousterhout] Remove input metrics for parallel collections
719f19d [Kay Ousterhout] Style fixes
bb6ec62 [Kay Ousterhout] Small fixes
869ac7b [Kay Ousterhout] Updated Json tests
44a0301 [Kay Ousterhout] Fixed accidentally added line
4bd0568 [Kay Ousterhout] Added input source, renamed Hdfs to Hadoop.
f27e535 [Kay Ousterhout] Updates based on review comments and to fix rebase
bf41029 [Kay Ousterhout] Updated Json tests to pass
0fc33e0 [Kay Ousterhout] Added explicit backward compatibility test
4e52925 [Kay Ousterhout] Added Json output and associated tests.
365400b [Kay Ousterhout] [SPARK-1683] Track task read metrics.
[SPARK-2104] Fix task serializing issues when sort with Java non serializable class

Details can be see in [SPARK-2104](https://issues.apache.org/jira/browse/SPARK-2104). This work is based on Reynold's work, add some unit tests to validate the issue.

@rxin , would you please take a look at this PR, thanks a lot.

Author: jerryshao <saisai.shao@intel.com>

Closes #1245 from jerryshao/SPARK-2104 and squashes the following commits:

c8ee362 [jerryshao] Make field partitions transient
2b41917 [jerryshao] Minor changes
47d763c [jerryshao] Fix task serializing issue when sort with Java non serializable class
SPARK-897:  preemptively serialize closures

These commits cause `ClosureCleaner.clean` to attempt to serialize the cleaned closure with the default closure serializer and throw a `SparkException` if doing so fails.  This behavior is enabled by default but can be disabled at individual callsites of `SparkContext.clean`.

Commit 98e01ae8 fixes some no-op assertions in `GraphSuite` that this work exposed; I'm happy to put that in a separate PR if that would be more appropriate.

Author: William Benton <willb@redhat.com>

Closes #143 from willb/spark-897 and squashes the following commits:

bceab8a [William Benton] Commented DStream corner cases for serializability checking.
64d04d2 [William Benton] FailureSuite now checks both messages and causes.
3b3f74a [William Benton] Stylistic and doc cleanups.
b215dea [William Benton] Fixed spurious failures in ImplicitOrderingSuite
be1ecd6 [William Benton] Don't check serializability of DStream transforms.
abe816b [William Benton] Make proactive serializability checking optional.
5bfff24 [William Benton] Adds proactive closure-serializablilty checking
ed2ccf0 [William Benton] Test cases for SPARK-897.