HADOOP-17483. Magic committer is enabled by default.

[steveloughran]

• core-default.xml updated
• CommitConstants updated
• All tests which previously enabled the magic commiter now rely on
  default settings. This helps make sure it is enabled.
• Docs cover the switch, mention its enabled and explain why you may
  want to disable it.

Change-Id: I40a24a34d519f412d5669ec7ca1de813ad071625

[steveloughran]

Tested: S3 london -Dparallel-tests -DtestsThreadCount=6 -Dmarkers=keep

Unbuffer test failure; also triggered a related failure in ITestS3AContractStreamIOStatistics

Filed: https://issues.apache.org/jira/browse/HADOOP-17499

These are network buffer related; read() calls returning less than the full buffer.

[liuml07]

+1

the change is indeed simpler than #2637

[steveloughran]

thanks. merged to 3.3+

[hadoop-yetus]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	34m 38s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	markdownlint	0m 1s		markdownlint was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚		0m 0s	test4tests	The patch appears to include 8 new or modified test files.
			_ trunk Compile Tests _
+0 🆗	mvndep	14m 8s		Maven dependency ordering for branch
+1 💚	mvninstall	20m 31s		trunk passed
+1 💚	compile	20m 31s		trunk passed with JDK Ubuntu-11.0.9.1+1-Ubuntu-0ubuntu1.20.04
+1 💚	compile	17m 44s		trunk passed with JDK Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
+1 💚	checkstyle	3m 49s		trunk passed
+1 💚	mvnsite	2m 26s		trunk passed
+1 💚	shadedclient	20m 11s		branch has no errors when building and testing our client artifacts.
+1 💚	javadoc	1m 42s		trunk passed with JDK Ubuntu-11.0.9.1+1-Ubuntu-0ubuntu1.20.04
+1 💚	javadoc	2m 21s		trunk passed with JDK Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
+0 🆗	spotbugs	1m 17s		Used deprecated FindBugs config; considering switching to SpotBugs.
+1 💚	findbugs	3m 34s		trunk passed
			_ Patch Compile Tests _
+0 🆗	mvndep	0m 26s		Maven dependency ordering for patch
+1 💚	mvninstall	1m 26s		the patch passed
+1 💚	compile	19m 47s		the patch passed with JDK Ubuntu-11.0.9.1+1-Ubuntu-0ubuntu1.20.04
+1 💚	javac	19m 47s		the patch passed
+1 💚	compile	17m 54s		the patch passed with JDK Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
+1 💚	javac	17m 54s		the patch passed
-0 ⚠️	checkstyle	3m 48s	/diff-checkstyle-root.txt	root: The patch generated 2 new + 28 unchanged - 0 fixed = 30 total (was 28)
+1 💚	mvnsite	2m 26s		the patch passed
+1 💚	whitespace	0m 0s		The patch has no whitespace issues.
+1 💚	xml	0m 1s		The patch has no ill-formed XML file.
+1 💚	shadedclient	13m 33s		patch has no errors when building and testing our client artifacts.
+1 💚	javadoc	1m 40s		the patch passed with JDK Ubuntu-11.0.9.1+1-Ubuntu-0ubuntu1.20.04
+1 💚	javadoc	2m 17s		the patch passed with JDK Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
+1 💚	findbugs	3m 48s		the patch passed
			_ Other Tests _
+1 💚	unit	17m 48s		hadoop-common in the patch passed.
+1 💚	unit	2m 3s		hadoop-aws in the patch passed.
+1 💚	asflicense	0m 58s		The patch does not generate ASF License warnings.
		228m 42s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-2656/1/artifact/out/Dockerfile
GITHUB PR	#2656
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient xml findbugs checkstyle markdownlint
uname	Linux c4bfbc05866f 4.15.0-60-generic #67-Ubuntu SMP Thu Aug 22 16:55:30 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	trunk / 7c4ef42
Default Java	Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.9.1+1-Ubuntu-0ubuntu1.20.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_275-8u275-b01-0ubuntu1~20.04-b01
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-2656/1/testReport/
Max. process+thread count	2891 (vs. ulimit of 5500)
modules	C: hadoop-common-project/hadoop-common hadoop-tools/hadoop-aws U: .
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-2656/1/console
versions	git=2.25.1 maven=3.6.3 findbugs=4.0.6
Powered by	Apache Yetus 0.13.0-SNAPSHOT https://yetus.apache.org

This message was automatically generated.