Using kernel bypass

In this section, we will discuss using the kernel bypass technique to improve the performance of User Datagram Protocol (UDP) sockets to process inbound market data updates from the exchanges and Transmission Control Protocol (TCP) sockets to send outbound order flow/requests to the exchange. Fundamentally, kernel bypass looks to eliminate the expensive context switches and mode switches between kernel mode and user mode as well as duplicate copying of data from the Network Interface Card (NIC) to user space, each of which ends up reducing the latency quite a bit.

Network processing driven by system calls/interrupts in the non-kernel bypass design, threads, or processes that want to read incoming data on UDP or TCP socket block on the read call, as described in the Understanding context switches – interrupt handling section in the previous chapter. That leads the blocked thread or process being context switched out, and then it is woken up by the interrupt...