Virtio/Block/Latency

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Revision as of 07:26, 3 June 2010 by Stefanha (talk | contribs)

This page describes how virtio-blk latency can be measured. The aim is to build a picture of the latency at different layers of the virtualization stack for virtio-blk.

Benchmarks

Single-threaded read or write benchmarks are suitable for measuring virtio-blk latency.

I use a simple sequential read C program which prints the average time per read operation at the end.

Instrumenting the stack

Guest

Guest virtio-pci

Host kvm

QEMU virtio

QEMU paio

Host pread64

Results

Host

Guest

Latency