Constant MAX_RX_BUFFERS 

pub const MAX_RX_BUFFERS: u32 = 818; // 818u32

The maximum number of RxBuffer structs that could be sent in a single FIDL message while staying within the maximum message size enforced by the bindings.

At the time of writing, FIDL messages are limited to 65 KiB. In the current FIDL wire format, the size of an RxBuffer is 80 bytes, and the fixed overhead of the CompleteRx request is 32 bytes (16 for the FIDL message header + 16 for the vector), so we selected the maximum N where 32

• N * 80 <= 65 KiB.