8293562: blocked threads with KeepAliveCache.get

[djelinski]

Please review this patch that makes sure KeepAliveCache does not block all threads while closing sockets.

Changes:

• get operation no longer closes sockets; if there's no socket that is recent enough, get returns null and lets the cleaner thread close the sockets
• put operation closes sockets without holding the cache lock. Additionally, if the cache is full, it places the new connection in the cache and removes the oldest connection.
• the cleaner thread creates a list of connections to close, and then closes them after releasing the cache lock
• additionally, we set the socket timeout to 1 millisecond before calling socket.close

The new test fails with Wait for second request timed out without this patch, passes after the changes. Tiers 1-3 clean.

---

Progress

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• Commit message must refer to an issue

Issue

• JDK-8293562: blocked threads with KeepAliveCache.get

Reviewers

• Daniel Fuchs (@dfuch - Reviewer) ⚠️ Review applies to 4410abf1
• Michael McMahon (@Michael-Mc-Mahon - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back djelinski! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@djelinski The following label will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 05: Full - Incremental (cf14dfed)
• 04: Full - Incremental (ab350fc6)
• 03: Full - Incremental (48a7ca17)
• 02: Full - Incremental (4410abf1)
• 01: Full - Incremental (1869c9aa)
• 00: Full (402e8f01)

[dfuch]

Very good work overall - but I believe we should set the SO_TIMEOUT only for SSLSockets (in the HttpsClient subclass) - and make sure we do it everywhere where serverSocket.close() is called.

[djelinski]

we should set the SO_TIMEOUT only for SSLSockets (in the HttpsClient subclass)

Done.

and make sure we do it everywhere where serverSocket.close() is called.

The only other place is checkURLSpoofing; I'd rather not touch that method here. It does not block the KeepAliveCache.

we should try catch and ignore exception

Done.

[openjdk]

@djelinski This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8293562: blocked threads with KeepAliveCache.get

Reviewed-by: dfuchs, michaelm

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 139 new commits pushed to the master branch:

• c2ce43c: 8291021: JFR: Only one finished state in ChunkHeader class
• f015733: 8294357: (tz) Update Timezone Data to 2022d
• 64da862: 8287597: List all preview features on the javadoc PREVIEW page
• b4e1e41: 8293000: Review running times of jshell regression tests
• 6d83482: 8293540: [Metrics] Incorrectly detected resource limits with additional cgroup fs mounts
• 6974978: 8294521: Parallel: Remove unused field in UpdateDensePrefixAndCompactionTask
• 81fda1b: 8294569: Remove CardTable::_last_valid_index
• 7c60e6d: 8293770: RISC-V: Reuse runtime call trampolines
• 9dce865: 8294115: JNI local refs exceeds capacity warning in NetworkInterface::getAll
• b030c7d: 8225235: Unused field defaultIndex in NetworkInterface
• ... and 129 more: https://git.openjdk.org/jdk/compare/bb422f5c14745bf29bc2cb741f819a17c8400543...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[Michael-Mc-Mahon]

Looks good!

[djelinski]

Thanks for the reviews!

/integrate

[openjdk]

Going to push as commit 03f25a9.
Since your change was applied there have been 152 commits pushed to the master branch:

• a69ee85: 8292336: JFR: Warn users if -XX:StartFlightRecording:disk=false is specified with maxage or maxsize
• b8b9b97: 8294676: [JVMCI] InstalledCode.deoptimize(false) should not touch address field
• fd59430: 8294610: java/net/vthread/HttpALot.java is slow on Linux
• c7ab1ca: 8294609: C2: Improve inlining of methods with unloaded signature classes
• 375f02f: 8294608: Remove redundant unchecked suppression in FileDescriptor
• d207da8: 8294533: Documentation mistake in Process::getErrorStream and getInputStream
• da4e96d: 8276545: Fix handling of trap count overflow in Parse::Parse()
• 48674d4: 8291428: JFR: 'jfr print' displays incorrect timestamps during DST
• 3b1bc21: 8294307: ISO 4217 Amendment 173 Update
• b8f9a91: 8293940: Some tests for virtual threads take too long
• ... and 142 more: https://git.openjdk.org/jdk/compare/bb422f5c14745bf29bc2cb741f819a17c8400543...master

Your commit was automatically rebased without conflicts.

[openjdk]

@djelinski Pushed as commit 03f25a9.

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