Storage I/O Performance on VMware vSphere 5.1 over 16 Gigabit Fibre Channel White Paper
Fibre Channel (FC) interconnect speed has increased to 16 gigabits per second (Gbps). To take full advantage of this enhancement, VMware vSphere® 5.1 has added support for the 16Gb FC host bus adapter (HBA). This white paper illustrates the improvements in storage I/O throughput that vSphere gains when using a 16Gb FC HBA instead of an 8Gb FC HBA. In addition, this paper looks at the CPU efficiency of the vSphere host when handling the increased storage I/O.
With the availability of 16Gb FC HBAs, larger block I/Os have doubled their throughput compared to the 8Gb per second bandwidth. The throughput has improved together with better CPU efficiency per I/O. For random I/Os with small block sizes, I/Os per second (IOPs) have increased because their throughput is not bounded by the FC link speed before reaching the 16Gbps wire speed limit.
Having doubled the throughput rates from the newly available 16Gb FC HBA, the vSphere 5.1 platform can support more storage devices and meet bandwidth requirements using the same number of FC links. The doubled bandwidth for large block transfers can benefit applications like VMware vSphere® Storage vMotion®. The improvement in random read IOPs at a 4KB block size, for example, can benefit application components like VMware® ViewTM clients. Applications are no longer limited by the existing 8Gb FC bandwidth to meet their peak performance requirements.
To learn more and to download the above file, please visit: Storage I/O Performance on VMware vSphere 5.1 over 16 Gigabit Fibre Channel