Perf in Netflix

Linux perf is a crucial performance analysis tool at Netflix, and is used by a self-service GUI for generating CPU flame graphs and other reports. This sounds like an easy task, however, getting perf to work properly in VM guests running Java, Node.js, containers, and...

Performance Analysis with BPF

The in-kernel Berkeley Packet Filter (BPF) has been enhanced in recent  kernels to do much more than just filtering packets. It can now run user-defined programs on events, such as on tracepoints, kprobes, uprobes, and perf_events, allowing advanced performance...

Fast by Friday: Why Kernel Superpowers are Essential

It is not ok that we speed weeks, even months, trying to solve why software is slow. Companies waste money on compute costs, users are unhappy with latency, and product evaluations run out of investigation time. It should not take more than a week to identify the root...

Faster & Fewer Page Faults

We have improved the Linux page fault mechanism to reduce the number of faults and handle them more quickly when they do happen. By managing memory in large folios, we reduce the number of page faults. The 4KiB page used on many architectures is simply too small for...