[improve][broker] Pin executor to managed ledger instance to cache the string hashing

[merlimat]

Motivation

In many operations we're hashing on the managed ledger name to ensure all the callbacks are triggered from same thread. Instead of hashing the string each, let's pin the thread and always use the same, for a given managed ledger instance.

This will avoid the hashing overhead.

Tests in https://github.com/merlimat/pulsar/pull/3

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• [X] doc-not-needed
• [ ] doc-complete

[github-actions[bot]]

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[codecov-commenter]

Codecov Report

Merging #18078 (66fc80a) into master (cee697b) will decrease coverage by 0.49%. The diff coverage is 19.42%.

@@             Coverage Diff              @@
##             master   #18078      +/-   ##
============================================
- Coverage     47.06%   46.56%   -0.50%     
- Complexity     8956    10342    +1386     
============================================
  Files           592      698     +106     
  Lines         56313    68326   +12013     
  Branches       5844     7332    +1488     
============================================
+ Hits          26503    31817    +5314     
- Misses        26946    32886    +5940     
- Partials       2864     3623     +759     

Flag	Coverage Δ
unittests	46.56% <19.42%> (-0.50%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...apache/bookkeeper/mledger/ManagedLedgerConfig.java	71.60% <0.00%> (ø)
.../org/apache/bookkeeper/mledger/impl/MetaStore.java	100.00% <ø> (ø)
...okkeeper/mledger/impl/ShadowManagedLedgerImpl.java	0.00% <0.00%> (ø)
...kkeeper/mledger/impl/cache/EntryCacheDisabled.java	10.86% <0.00%> (ø)
...ava/org/apache/pulsar/broker/service/Consumer.java	70.28% <0.00%> (+8.18%)	:arrow_up:
...ker/stats/prometheus/NamespaceStatsAggregator.java	0.00% <0.00%> (ø)
...va/org/apache/pulsar/client/impl/ProducerImpl.java	17.00% <0.00%> (-0.02%)	:arrow_down:
...rg/apache/pulsar/broker/service/BrokerService.java	57.50% <20.00%> (+0.31%)	:arrow_up:
...sar/broker/service/persistent/PersistentTopic.java	61.12% <20.00%> (-1.16%)	:arrow_down:
...ava/org/apache/pulsar/broker/service/Producer.java	61.75% <27.27%> (-2.15%)	:arrow_down:
... and 191 more

[poorbarcode]

/pulsarbot rerun-failure-checks

[tisonkun]

/pulsarbot rerun-failure-checks