XDP (eXpress Data Path) is the new programmable in-kernel fast-path, which is placed as a layer before the existing Linux kernel network stack (netstack). We claim XDP is not kernel-bypass, as it is a layer before and it can easily fall-through to netstack. Reality is...
As the name would suggest, a Non-Maskable Interrupt (NMI) is an interrupt-like feature that is unaffected by the disabling of classic interrupts. In Linux, NMIs are involved in some features such as performance event monitoring, hard-lockup detector, on demand state...
Traditionally processes are identified globally via process identifiers (PIDs). Due to how pid allocation works the kernel is free to recycle PIDs once a process has been reaped. As such, PIDs do not allow another process to maintain a private, stable reference on a...
RCU has seen lots of changes in the last 2 years. Of note is the RCU flavor consolidation and tree RCU’s lock contention improvements. There have been also improvements with static checking, fixes to scheduler deadlocks and improvements to RCU-based linked lists....
Operating system distributors often face challenges that are somewhat different from that of upstream kernel developers. For instance, some kernel updates often need to stay at least binary compatible with modules that might be “out of tree” for some time. In that...
