Is it possible to ignore WS message payload in Channels?

I’m trying to establish a speed test where I send a large payload in websocket message to a Phoenix backend. Currently, the payload is in JSON as expected, and is surely being parsed into Elixir terms on the backend when received. Since I’m sending a large message (several Mb) I’m wondering if the processing/parsing time might be affecting my measurement.

Is is possible to have the server logic ignore the WS message and just respond when something/anything arrives? Would binary messages be a good candidate for this?

Thanks for any info!