SAN JOSE, Calif. Two startups debut Monday (March 31), together giving virtualization a new twist to help create large systems made up from multiple x86 servers. 3Leaf Systems is designing ASICs as part of its approach while ScaleMP creates the links via software alone.
Hosting multiple operating systems on a single server is the focus for most virtualization products. The startups flip that notion on it ahead to stretch a single operating system across as many as 16 servers, in effect creating a powerful symmetric multiprocessing system out of low-cost PC server motherboards.
3Leaf has licensed Intel Corp.'s new processor bus, the QuickPath Interconnect, as one ingredient in an ASIC that creates cache coherent links between servers. The company is still working on an architectural design for the chip which may not be available until 2010.
Separately, the company expects to deliver by mid-2009 a version of the ASIC using the coherent HyperTransport bus of Advanced Micro Devices. First silicon for chips using the AMD bus came back from the fab in February.
Both 90nm ASICs will essentially look like another processor on a server motherboard but consume just 15W. They will establish cache coherent links to other boards using generic networking blocks that can mimic a 10 Gbit/s Ethernet or 20 Gbit/s Infiniband connection.
"Our chip basically extends the coherency domain from a single server to a set of servers," said Bob Quinn, founder and chief technologist of 3Leaf. "The operating system is protected from seeing the variety of physical servers via our distributed hypervisor," he added.
The extended domain can embrace as many as 64,000 servers. One Linux or Windows Server operating system image can span up to 16 systems and a terabyte of memory. The company plans a second-generation chip that can put 256 Tbytes RAM under one OS.
Users will be able to write policies that set for an application the minimum and maximum hardware resources it can access. Quinn claims the approach can optimize how a single app is shared across pools of CPUs, memory and I/O more easily and effectively than existing software virtualization tools.
3Leaf is negotiating with chip partners who will make its ASICs under license. The company has raised $32.5 million to date from investors including Intel Capital.
The startup has deployed with about a dozen beta users an early version of its technology that virtualizes just the I/O. It is delivered as software running on an x86-based appliance with no special hardware. The appliance acts as a sort of I/O gateway between a bank of servers and network and storage switches, increasing the utilization rate of network links and redundant servers.
"Rarely do we see Fibre Channel storage connections with more than a five percent utilization rate, so our appliance can lower capital expenses by driving up utilization," said Quinn, a serial entrepreneur who has launched startups in EDA and network processing.
Quinn said the idea for his startup came from noticing several technology trends fall into place.
He noticed with the rise of mainstream 64-bit processors how vendors started offering to hypervisor software vendors access to new privileged execution areas bellow the so-called ring 0 of the operating system. At the same time, interconnects such as Infiniband began offering latency and bandwidth capabilities that made them suitable for carrying a cache coherent link between systems. Finally, operating systems began to build in the software structures needed to support non-uniform memory access, a technology widely deployed in large custom-built multiprocessing systems.
"This is what 3Leaf needed to ensure we could do this with no software changes to the OS or applications," Quinn said.