Integration with KVM/QEMU

By now, you may have heard about the recent work being done to integrate GlusterFS with QEMU. The engineers at IBM’s Linux Technology Center in Bangalore deserve a lot of credit for their work here. Bharata Rao, Deepak Shetty and Mohan Kumar have been hard at work implementing a GlusterFS device driver for QEMU that bypasses FUSE, talking directly to GlusterFS via a new client library, libgfapi. This is truly exciting stuff, and one of the things that will make GlusterFS 3.4 a significant advance for anyone with scale-out, virtualized environments.

Bharata Rao wrote a quite informative blog post on the subject, relating how they were solving the problem and what performance gains could be expected. The difference in performance is quite striking, with almost 3x improvement in sequential reads and almost 2x improvement in sequential writes. This is pretty significant and will, we hope, convince more users to go big with GlusterFS.

If you want to try out the new code, you’ll have to check out the latest master branch for GlusterFS from our git repo and download the release candidate for QEMU 1.3. You’ll also need the most recent version of libvirt. Expect a beta release of GlusterFS 3.4 in the near future. QEMU 1.3 is targeted for release in December, and GlusterFS 3.4 should be out in January.

For more information on the subject, see Mohan’s abstract from LinuxCon Europe and Bharata Rao’s slides and YouTube tutorials.

Highly recommended: read Bharata Rao’s comprehensive blog post.