release-23.1: allocator: remove log.VEventf for alive stores in isStoreReady…

[blathers-crl]

Backport 1/1 commits from #107420 on behalf of @wenyihu6.

/cc @cockroachdb/release

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When investigating an allocator simulator test, we observed a significant amount
of time spent by log.VEventf, consuming 64% of time (according to pprof CPU
analysis). This was mainly caused by rankedCandidateListForRebalancing
repeatedly calling IsStoreReadyForRoutineReplicaTransfer on all stores that
pass the StoreFilterThrottled filter. As a temporary mitigation, we deleted
log.VEventf in isStoreReadyForRoutineReplicaTransferInternal for less
interesting cases where stores are alive. However, our longer term strategy is
to buffer such outputs in the allocator at a higher level to reduce
log.VEventf calls.

Informs: #107421

Release note: None

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Before	After

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Release justification: Removes significant logging overhead in clusters with a large number of stores.

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

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[blathers-crl]

It looks like your PR touches production code but doesn't add or edit any test code. Did you consider adding tests to your PR?

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[cockroach-teamcity]

This change is