There’s nothing worse than having memory problems. Remember Ten Second Tom in 50 First Dates? He had a terrible quality of life because of his memory issues. Juxtapose this with the awesome life of Sheldon Cooper from Big Bang Theory, who has an eidetic memory. He’s got a great job, good friends, and can remember all kinds of fun facts about the U.S. Interstate System.
The same can be said for network infrastructure. Much of the focus on network infrastructure tends to be on things like port density, backplane speeds, and other transport-related things. This makes sense given that’s the role of a networking product. However, much of what a network device does is held in memory. Slow memory can cause significant performance problems in the network. No matter how much horsepower the rest of the box itself has, memory issues will cause performance problems.
The problem is continuing to get worse as well. Network speeds have been increasing exponentially. We went from 10 MB to 100, to 1 Gig then 10 Gig, and now 100 Gig is on the horizon. There are a couple intermediate steps around 25 Gig and 40 Gig, but these are just steps along the path to 100. Pretty soon we’ll be talking about 400 Gig- or TB-speed networking devices.
Memory performance, however, has followed along linear lines, creating a widening gap between exponential network growth and linear memory performance improvements. The net result is that traditional memory in ASIC switch chips just cannot keep up with the increased demand for network speeds, port density, and programmability capabilities.
The massive amount of inbound data is only part of the problem created by the growing memory – network gap. The packet processor performs a number of tasks based on the header and payload of each data packet. Each of these tasks requires access to the memory in the ASIC. The current memory solutions require a number of expensive workarounds to keep performance up.
Cisco’s latest acquisition, Memoir Systems, addresses this challenge. The company licenses soft-logic IP, which accelerates physical memory by a factor of 10 while also lowering the real estate required for the memory in the ASIC. The improved memory capabilities enable the development of network ASICs with speeds, density, and costs that just can’t be met with traditional memory designs. This differentiation becomes increasingly important as network speeds jump and as vendors look to increase the density of ports on a switch.
Memoir Systems is able to do this through something the company calls “algorithmic memory.” Instead of having a single operation-per-clock cycle, Memoir has 10 ports that can simultaneously access independent addresses in the same memory bank, in the same clock cycle at full speeds. So for a 500-Mhz system, traditional memory can do 500 million memory operations per second where the Memoir solution can do 5000, an order of magnitude improvement, even though the physical memory is still running at 500 Mhz.
The Memoir technology is already being used in the Nexus 9000 switches and Cisco told me on a pre-brief that it has been designed into other Cisco products, although they wouldn’t say which ones. It makes sense that this would wind up in other data center products such as MDS, as well as others with high-speed interfaces, such as telco routers and security devices.
In the short term, though, Memoir Systems will be used to create differentiation for Cisco’s data center products and will report into the Cisco Insieme Business Unit led by SVP Mario Mazzola. The addition of Memoir is a good example of how Cisco is able to build differentiated systems and stay ahead of the commoditization curve in networking.