VMware, Inc.
ENHANCED NETWORK STACK

Abstract:

Some embodiments of the invention provide a new networking data path framework that employs one or more dedicated kernel threads to process network traffic on a host computer executing multiple machines (such as virtual machines or containers). This new framework is referred to as an Enhanced Networking Stack (ENS) in this document. In some embodiments, the dedicated kernel threads execute on dedicated CPU cores (e.g., one kernel thread per CPU core) to proactively poll physical NICs (PNICs) of the host computer and virtual NICs (VNICs) of the machines (e.g., VMs), and to perform packet processing operations on packets received by the host and packets transmitted by the machines. In some embodiments, each PNIC or VNIC is associated with one dedicated kernel thread, in order to avoid synchronization issues between the kernel threads. In the discussion below, these kernel threads are referred to as fast-path packet processing threads or as logical cores, or Lcores, and the physical and virtual NICs that are polled by the Lcores are referred to as polled network devices. In some embodiments, one Lcore can process multiple polled network devices. This is beneficial because in some embodiments one CPU core is dedicated to each Lcore (i.e., because one Lcore monopolizes the entire computing power of one CPU core), and it would be wasteful to dedicate one Lcore to just one polled network device, which might be underutilized.