About wiki of `NiFi's Write-Ahead Log Implementation`

[????????]

Hello!
Yesterday, I saw the wiki of `NiFi's Write-Ahead Log Implementation`. I saw 
below:


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Verify records have been restored ('restored flag' set to true). If not, throw 
IllegalStateException

Obtain repo shared lock (read lock)

Claim a partition that is not currently in use
Increment an AtomicLong and mod by the number of partitions -> partitionIndex

Try to claim (obtain a write lock on) partition[partitionIndex]. If not 
successful, go back to 2a.




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Is this `2a` pointed to the Step 2(Obtain repo shared lock (read lock)) or 
the 3a?


Best Regards??


Thanks!