HDFS-13538. HDFS DiskChecker should handle disk full situation

[shkhrgpt]

Description of PR

DiskChecker was enhanced to do checking with some i/o in HADOOP-13738. But this was rolled back partially because of fsync issue seen in HADOOP-15450 and the problem of disk full being flagged as a check failure (HDFS-13538).

This PR tries to address HDFS-13538 and enable i/o based disk checking ONLY for HDFS with a flag that can be turned on in dfs configs.

How was this patch tested?

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running org.apache.hadoop.util.TestDiskCheckerWithDiskIo
[INFO] Tests run: 6, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.129 s -- in org.apache.hadoop.util.TestDiskCheckerWithDiskIo
[INFO] 
[INFO] Results:
[INFO] 
[INFO] Tests run: 6, Failures: 0, Errors: 0, Skipped: 0


[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  35:00 min
[INFO] Finished at: 2025-08-29T01:17:06+05:30
[INFO] ------------------------------------------------------------------------

For code changes:

• Does the title or this PR starts with the corresponding JIRA issue id (e.g. 'HADOOP-17799. Your PR title ...')?
• Object storage: have the integration tests been executed and the endpoint declared according to the connector-specific documentation?
• If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under ASF 2.0?
• If applicable, have you updated the LICENSE, LICENSE-binary, NOTICE-binary files?

[hadoop-yetus]

💔 -1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	25m 24s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 0s		codespell was not available.
+0 🆗	detsecrets	0m 0s		detect-secrets was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚	test4tests	0m 0s		The patch appears to include 1 new or modified test files.
			_ trunk Compile Tests _
+0 🆗	mvndep	9m 10s		Maven dependency ordering for branch
+1 💚	mvninstall	36m 27s		trunk passed
+1 💚	compile	18m 57s		trunk passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	compile	17m 41s		trunk passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	checkstyle	4m 59s		trunk passed
+1 💚	mvnsite	3m 11s		trunk passed
+1 💚	javadoc	2m 51s		trunk passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	3m 16s		trunk passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	6m 19s		trunk passed
+1 💚	shadedclient	45m 16s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+0 🆗	mvndep	0m 33s		Maven dependency ordering for patch
+1 💚	mvninstall	2m 24s		the patch passed
+1 💚	compile	18m 20s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javac	18m 20s		the patch passed
+1 💚	compile	15m 12s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	javac	15m 12s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	4m 38s		the patch passed
+1 💚	mvnsite	3m 5s		the patch passed
+1 💚	javadoc	2m 29s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	2m 47s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	6m 32s		the patch passed
+1 💚	shadedclient	44m 57s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	24m 4s		hadoop-common in the patch passed.
-1 ❌	unit	218m 3s	/patch-unit-hadoop-hdfs-project_hadoop-hdfs.txt	hadoop-hdfs in the patch passed.
+1 💚	asflicense	1m 36s		The patch does not generate ASF License warnings.
		518m 46s

Reason	Tests
Failed junit tests	hadoop.tools.TestHdfsConfigFields
	hadoop.hdfs.tools.TestDFSAdmin

Subsystem	Report/Notes
Docker	ClientAPI=1.51 ServerAPI=1.51 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-7918/1/artifact/out/Dockerfile
GITHUB PR	#7918
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets
uname	Linux 13cb127ba18e 5.15.0-144-generic #157-Ubuntu SMP Mon Jun 16 07:33:10 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	trunk / 1b4b9f8
Default Java	Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-7918/1/testReport/
Max. process+thread count	3098 (vs. ulimit of 5500)
modules	C: hadoop-common-project/hadoop-common hadoop-hdfs-project/hadoop-hdfs U: .
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-7918/1/console
versions	git=2.25.1 maven=3.6.3 spotbugs=4.2.2
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