Steve, try glusterfs 3.3 and look at: http://community.gluster.org/a/linux-kernel-tuning-for-glusterfs/ There will be more optimizations in the next Gluster release. Take advantage of the translators that Gluster supplies, including readahead translator and quick-read translator. Red Hat does offer support for Red Hat Storage based on Gluster, and it has a pre-packaged tuning profile built into it. We test with 10-GbE networks and Gluster 3.3 does have reasonably good performance for large-file sequential workloads (and it's scalable).
