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For serverStatus(), are thread activity tickets used when flowControl is not triggered?

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In the output of the serverStatus() command, there is output called flowControl.isLagged. Where "isLagged" is the condition for triggering flow control. When flow control is triggered, the docs say

writes on the primary must obtain tickets before taking locks

But the datadoghq.com web page says the following about wiredTiger.concurrentTransactions (tickets) stats:

The WiredTiger engine uses a ticketing system that aims to control the number of threads in use since they can starve each other of CPU. Tickets are an internal representation for thread management. They correspond to the number of concurrent read / write operations allowed into the WiredTiger storage engine.

So my question is, if flow control is not triggered (flowControl.isLagged is false), are the tickets talked about in wiredTiger.concurrentTransactions not used? I think the answer is "no" (ie., wiredTiger.concurrentTransactions tickets are always in use), but then the documentation would seem to be inconsistent. Or maybe there are two different types of tickets?

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