should compression be measured?

[domino14]

The following is a trace of an API request. Note the "uncovered" time at the end. If I turn compression off, this uncovered time shrinks by a quite a bit (around 2 ms total)

I'd love to see exactly what's taking this response that much longer. It seems like ~10K of data should compress in faster than 2 ms, but I'm actually not sure how long that takes.