worker.postMessage performance #38780

I'm using worker.postMessage(myString) to send data to my worker. However, I'm getting significant performance overhead from postMessage. I'm spending 16% of my total cpu time here. The strings are usually quite short but can be up to 256 chars.

Where does the overhead of postMessage mostly come from and is there ways to improve it? I might be intersted in trying to improve it if someone could point me in the right direction.

I've been consdering using a SharedArrayBuffer and writing the strings into the buffer and then Atomics.wait/notify, However, that feels wrong as it basically just re-implements what postMessage could/should be doing anyway. Is MessageChannel faster?