Of course Dave is always right, but like my wife always says: "Trust is good, but control is better...". So to gather some evidence, I have quickly debugged where the chunks (in the "data" event of the Exec-node) are coming from. Seems the chunks have indeed already a size of 65K when the come out of the socket:
So my highWaterMark level of 128K is never reached, and has no effect at all...
And for the non-believers among us, here is an extra explanation from the NodeJs team, that the chunk size is determined by the operating system.
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