On 07/10/2013 02:36 PM, Joe Julian wrote: > 1) http://www.solarflare.com makes sub microsecond latency adapters that > can utilize a userspace driver pinned to the cpu doing the request > eliminating a context switch We've used open-onload in the past on Solarflare hardware. And with GlusterFS. Just say no. Seriously. You don't want to go there. > 2) http://www.aristanetworks.com/en/products/7100t is a 2.5 microsecond > switch Neither choice will impact overall performance much for GlusterFS, even in heavily loaded situations. What impacts performance more than anything else is node/brick design, implementation, and specific choices in that mix. Storage latency, bandwidth, and overall design will be more impactful than low latency networking. Distribution, kernel and filesystem choices (including layout, lower level features, etc.) will matter significantly more than low latency networking. You can completely remove the networking impact by trying your changes out on localhost, and seeing what the impact your design changes have. If you don't start out with a fast box, you are not going to have fast aggregated storage. This observation has not changed since the pre 2.0 GlusterFS days (its as true today as it was years ago). -- Joseph Landman, Ph.D Founder and CEO Scalable Informatics, Inc. email: landman at scalableinformatics.com web : http://scalableinformatics.com http://scalableinformatics.com/siflash phone: +1 734 786 8423 x121 fax : +1 866 888 3112 cell : +1 734 612 4615