How deeply does Latency cover kernel bypass?

Compares userspace stacks, hardware access, and NIC offload, but provides no setup steps or measurements.

Kernel bypass

As explained in Latency

Kernel bypass is a networking technique in which application or userspace code accesses network hardware without routing packet processing through the operating-system kernel.

Kernel-bypass networking reduces network-data-path overhead by moving packet processing out of the operating-system network stack. It can avoid kernel crossings, context switches, copies, and per-packet allocation costs. section 3.3.3 section 7.5.3

Packet processing can move to different places:

Userspace software can implement the TCP/IP stack and receive packets directly into userspace memory. section 3.3.3
Hardware approaches include RDMA, which enables direct access to memory on another machine, and SR-IOV, which exposes virtual NICs to virtual machines. section 3.3.3
NIC offload can move protocol processing or application logic onto the NIC. XDP supports programmable packet processing early in the network path, either in the Linux kernel or on dedicated hardware. section 3.3.3

Userspace TCP/IP

F-Stack runs the FreeBSD network stack in userspace with DPDK, allowing an application to process packets without sending them through the kernel network stack. section 3.3.3

How Latency covers it

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Related concepts

network stackcontrasts with · A network stack is a layered set of protocols and software or hardware components that enables communication between applications and networked systems.
packet processing latencyaddresses · Packet processing latency is the delay between a network packet arriving at a network interface and becoming available to a userspace thread for processing.

This explainer was generated by Manning's knowledge graph from the text of Latency. The section links point to the parts of the book it draws on.