[improve][broker] Improve knownBrokers update in ModularLoadManagerImpl

[AnonHxy]

Motivation

Improve knowBrokers update

Modifications

Improve knowBrokers update

Verifying this change

• Make sure that the change passes the CI checks.

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: AnonHxy#37

[Technoboy-]

/pulsarbot rerun-failure-checks

[He-Pin]

knownBrokers？

[lifepuzzlefun]

@AnonHxy hi i found some previous fix on the ConcurrentModificationException when on knownBrokers field.
and in my opinion this method will have a chance to execute concurrently.
So if thread1 is try to figure out which is newAddBroker and which is deadBroker. thread2 clear the Collection will there an missing update？maybe an synchronized is need WDYT？

[AnonHxy]

knownBrokers？

Great. Have corrected the title. Thanks

[AnonHxy]

@AnonHxy hi i found some previous fix on the ConcurrentModificationException when on knownBrokers field. and in my opinion this method will have a chance to execute concurrently. So if thread1 is try to figure out which is newAddBroker and which is deadBroker. thread2 clear the Collection will there an missing update？maybe an synchronized is need WDYT？

Make sense