Chelsio Demonstrated 40GbE iSCSI Performance

Chelsio Communications, Inc. demonstrated the benefits of its T5 line of protocol offload adapters that make them an performing 40GbE iSCSI HBAs at Flash Memory Summit in Santa Clara, CA.

Showcasing the iSCSI hardware offload capabilities of company’s T5 40Gb/s Unified Wire adapters, the demonstration has show how all-flash and hybrid storage array OEMs can enable such arrays with iSCSI target performance that is fully compatible with the existing iSCSI ecosystem and supports the routability, scalability and reach advantages of iSCSI.

Chelsio T580-CR

The demonstration compared company’s T580-CR and Intel’s XL710 ‘Fortville’ server adapters running at 40Gb/s. The results confirm that T580 provides superior iSCSI performance, lower CPU utilization, higher throughput and lower latency, with small I/O performance. The T580 delivers line rate 40Gb/s at the I/O sizes that are more representative of actual application use (see benchmark report).

“Our T5 Unified Wire adapters enable an extremely high performance iSCSI storage target solution that is also very efficient,” said Jim Johnston, senior director, marketing, Chelsio. “Chelsio’s iSCSI offload technology enables 40 GbE to completely supplant proprietary storage fabrics, without requiing the deployment of new protocols that force an infrastructure forklift upgrade – exactly what the industry needs. We’re continuing to push the price-performance curve and delivering industry-leading solutions for the flash storage array market.“

iSCSI vs. iSER
iSCSI, the Internet SCSI standard, is an Ethernet SAN protocol, with native initiator support integrated into all the major OSs, and offers built-in RDMA for high performance offloaded implementations which, unlike the iSER (iSCSI over RDMA) protocol, does not break compatibility with the existing iSCSI ecosystem.

The high-performance enabled by company’s hardware offloaded iSCSI removes the need to forgo iSCSI’s installed base to achieve high performance. Benchmarking results demonstrate that iSCSI at 40Gb/s provides the same performance in throughput and CPU utilization as iSER, thanks to built-in RDMA that is optimized for SCSI storage. iSCSI preserves existing equipment without requiring a fabric overhaul, additional acquisition and management costs, with a high performance option thanks to hardware offload, and a strong roadmap to 100Gbps and beyond. iSER, on the other hand, adds unnecessary layers, and is merely a way for RDMA fabrics to offer iSCSI emulation, that is incompatible with the installed software base (see benchmark report).

“The iSER protocol was developed for non-Ethernet fabrics that have inefficient support for the Internet Protocol (IP) stack but provides little benefit compared to hardware offloaded iSCSI for Ethernet networks,” says Saqib Jang, principal and founder, Margalla Communications. “Unlike iSCSI, which is natively supported in all major OSs, iSER suffers from significant interoperability and deployability challenges.“