All Bark and no Bite: vCPU Stall Detection for KVM Guests - Sebastian Ene, Google
Channel: The Linux Foundation
Date: 2022-10-08

All Bark and no Bite: vCPU Stall Detection for KVM Guests - Sebastian Ene, Google

Is your VM performing poorly? Are its vCPU threads constantly runnable? Are you wondering whether it's doing anything useful at all? If so, then this is a job for the para-virtualised vCPU stall detector device!  This talk will introduce a per-VCPU virtual stall detector device, describing its watchdog-like design, interaction with steal time accounting and its implementation in crosvm along with the corresponding Linux kernel driver. This device is planned to be used in future versions of Android for detecting and reporting VM hangs on the host.