InFlightLimit

A node's bound on the commands in flight in its executors (wow.executor.max-in-flight): those taken and not finished, waiting in their lanes or in the kernel. The executors of every context on a node share one, so it bounds the node's memory and the work it queues ahead of its stores, whichever aggregates the commands are for.

The default, DEFAULT_MAX, is sized by Little's law for a slow store: a node whose store commits a few thousand appends a second (a connection pool of tens at a few milliseconds each, the backend's group commit on top) drains 4096 commands in one to two seconds, well within the default 10-second wait; beyond that, queueing longer only turns into wait timeouts, and an early 429 lets the client back off instead. A node with more cores or a larger pool raises it.