Parallelize per-instance listener registration during controller leadership [CICP-34606] - #193

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kabragaurav:gkabra/CICP-34606/parallel-inithandlers

Commits on Aug 14, 2026

Parallelize CallbackHandler registration in initHandlers() [CICP-34606]

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8e74c03
Fix: remove unused imports, add daemon thread naming for initHandlers pool

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56f8fa6
Add comment explaining parallelism constant choice

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f40f78d
Clean up test: use static imports, remove redundant comment

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3753d7a
Test null/empty handlers with real method, not mock default

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d3c979f
Fix deadlock: release synchronized(this) before calling handler.init()

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b26f7b9
Clarify comment: threads share one ZK connection, no new connections created

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307e1ad
Add benchmark test for initHandlers with real ZK

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9694bc5
Remove benchmark test from PR - used for local comparison only

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609bb9f
Add timing log to initHandlers for production observability

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79e4e37
Parallelize per-instance listener registration during controller leadership [CICP-34606]

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f709270
Fix deadlock: move parallel registration out of invoke() lock scope

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d254777
Fix stale Javadoc reference and remove unnecessary LinkedHash imports

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34ee708
Fix stale inline comment and remove unused imports from tests

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ad8c711
Remove TestParallelListenerRegistrationBenchmark from PR

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65f08a6
Remove redundant PendingInstanceListeners tests from TestInitHandlersParallel

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e53282e
Skip already-initialized handlers in initHandlers to avoid spurious WARN logs

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92c0d72
Cap initHandlers parallelism at 10 (was 20) to bound concurrent ZK requests

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45fd807
Remove timing estimates from initHandlers/addListener comments

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4cb02f9
Fix failover path: register deferred per-instance listeners on CALLBACK leadership acquisition

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dfb7686
Address review: bounded retry on transient registration failure + end-to-end observability

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b0f74ec
Register deferred listeners from a single hook covering every leadership path

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ce09cda
Keep _lastSeen* consistent with what actually registered (review: Pratyush)

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82c7ecd
Harden async registration: close the observation window + bound the worker thread

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5c1524f
Drop the redundant post-registration refresh (self-review)

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17034d2
Hygiene: extract runTasksInParallel helper; fix stale handleNewSession comment

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7e1e201
Docs: make three comments accurate to what the code actually does (no behavior change)

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36bfd59
Fix import order: RejectedExecutionException after Future (checkstyle/convention)

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1137b85

Commits on Aug 17, 2026

Make initHandlers parallelism configurable via system property

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0b6ba52

Commits on Aug 18, 2026

Contain blast radius, gate behind a flag, and fix reconnect regression [CICP-34606]

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d88bc4f
Rename pool-size flag into the feature namespace; harden test flag isolation [CICP-34606]

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30be3cb
Add thread-count cap and a spectator containment test [CICP-34606]

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1b630c5
Add real-ZK failover validation harness (server-side wchp watch counts) [CICP-34606]

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9f37007

Commits on Aug 19, 2026

Remove ticket refs from code/tests and drop test stdout noise

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f7f6a02