The http client sends headers and the request body in separate packets. This can cause additional slowness with any network latency, particularly with TCP_NODELAY not being enabled or configurable (WEJBHTTP-144) . The split packet is from the headers first writing here, calling processWrite without a gathering write. The response body is passed in to the HttpRequestConduit.write but only gets written out right after the headers here. Would we consider passing on the srcs data to the processWrite call so we can write both headers and the available body at once in a single packet?