PowerKVM Performance: Tuning a full-system guest
jhopper 270000YPM8 Visits (8514)
By: Jenifer Hopper
This article explains an example method to tune a full-system PowerKVM guest to achieve CPU and memory performance that is very close to non-virtualized speeds, demonstrating very low KVM overhead on a POWER8 system. It also provides some common tuning tips for running SPECjbb2005 and the STREAM memory bandwidth workload on POWER8 systems.
The example tutorial starts by measuring non-virtualized performance to provide a system baseline (non-virtualized mode is currently a technical preview), then tests PowerKVM performance using both an "out of the box" and a "tuned" full-system guest configuration, describing how applying some common guest tuning to pin the vCPUs and memory can help achieve near-baremetal performance for some workload scenarios.