HBASE-28934: Avoid waits within HFilePreadReader constructors for cache initialisation.

[jhungund]

The current implementation is such that the HFilePreadReader constructor waits for the cache initialisation to decide whether or not, to create a prefetcher for an HFile.

However, as the HFilePreadReader constructor waits for the bucket cache initialisation, it blocks the region from bein opened. Any calls to read from the region fail until the cache is initialised.

This prevents the region from being usable, which otherwise, can read from the data store (cloud storage) to serve the client requests.

This change prevents the waits with the HFilePreadReader constructor and instead, move this wait to the prefetch thread, which waits until the cache is initialised to decide whether or, not to prefetch the file. Any requests to the regions will be served from the main data store instead of cache.

Also, the missed cache access during the cache initialisation should be accounted for the cache misses.

Change-Id: I952c592a1020874ad874f1909f776d8652375a1b

[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 40s		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 💚	hbaseanti	0m 0s		Patch does not have any anti-patterns.
			_ master Compile Tests _
+1 💚	mvninstall	2m 57s		master passed
+1 💚	compile	2m 54s		master passed
+1 💚	checkstyle	0m 37s		master passed
+1 💚	spotbugs	1m 33s		master passed
+1 💚	spotless	0m 44s		branch has no errors when running spotless:check.
			_ Patch Compile Tests _
+1 💚	mvninstall	2m 48s		the patch passed
+1 💚	compile	2m 58s		the patch passed
+1 💚	javac	2m 58s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
+1 💚	checkstyle	0m 36s		the patch passed
+1 💚	spotbugs	1m 40s		the patch passed
+1 💚	hadoopcheck	10m 18s		Patch does not cause any errors with Hadoop 3.3.6 3.4.0.
+1 💚	spotless	0m 43s		patch has no errors when running spotless:check.
			_ Other Tests _
+1 💚	asflicense	0m 11s		The patch does not generate ASF License warnings.
		35m 2s

Subsystem	Report/Notes
Docker	ClientAPI=1.47 ServerAPI=1.47 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6389/1/artifact/yetus-general-check/output/Dockerfile
GITHUB PR	#6389
JIRA Issue	HBASE-28934
Optional Tests	dupname asflicense javac spotbugs checkstyle codespell detsecrets compile hadoopcheck hbaseanti spotless
uname	Linux 630e4fe1adb5 5.4.0-195-generic #215-Ubuntu SMP Fri Aug 2 18:28:05 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / a2a1d88
Default Java	Eclipse Adoptium-17.0.11+9
Max. process+thread count	84 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6389/1/console
versions	git=2.34.1 maven=3.9.8 spotbugs=4.7.3
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[Apache-HBase]

💔 -1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	0m 44s		Docker mode activated.
-0 ⚠️	yetus	0m 2s		Unprocessed flag(s): --brief-report-file --spotbugs-strict-precheck --author-ignore-list --blanks-eol-ignore-file --blanks-tabs-ignore-file --quick-hadoopcheck
			_ Prechecks _
			_ master Compile Tests _
+1 💚	mvninstall	3m 1s		master passed
+1 💚	compile	0m 56s		master passed
+1 💚	javadoc	0m 30s		master passed
+1 💚	shadedjars	5m 10s		branch has no errors when building our shaded downstream artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	2m 51s		the patch passed
+1 💚	compile	0m 56s		the patch passed
+1 💚	javac	0m 56s		the patch passed
+1 💚	javadoc	0m 29s		the patch passed
+1 💚	shadedjars	5m 6s		patch has no errors when building our shaded downstream artifacts.
			_ Other Tests _
-1 ❌	unit	246m 24s	/patch-unit-hbase-server.txt	hbase-server in the patch failed.
		270m 59s

Subsystem	Report/Notes
Docker	ClientAPI=1.47 ServerAPI=1.47 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6389/1/artifact/yetus-jdk17-hadoop3-check/output/Dockerfile
GITHUB PR	#6389
JIRA Issue	HBASE-28934
Optional Tests	javac javadoc unit compile shadedjars
uname	Linux 4fdbfe84e1c3 5.4.0-195-generic #215-Ubuntu SMP Fri Aug 2 18:28:05 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / a2a1d88
Default Java	Eclipse Adoptium-17.0.11+9
Test Results	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6389/1/testReport/
Max. process+thread count	4601 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-6389/1/console
versions	git=2.34.1 maven=3.9.8
Powered by	Apache Yetus 0.15.0 https://yetus.apache.org

This message was automatically generated.

[wchevreuil]

UT failure looks unrelated.