MorphLabs has designed x86 infrastructure, loaded with OpenStack cloud software, that will ship as integrated racks of blade servers, network switches, and storage, something like VCE's Vblocks, HP's Converged Cloud, or Dell's vStart.
But MorphLabs announced Wednesday that it will substitute massive amounts of solid state disk (SSD) for spinning disk drives in its mCloud Rack Enterprise Edition, which eliminates the need for an attached storage area network (SAN) in a customer's cloud infrastructure, Damarillo said in an interview. Eliminating the SAN cuts out a major cost of establishing a private cloud with associated virtualized storage, he said.
The design also is optimized for the concentration and performance of virtual machine workloads. It's possible for a half rack to run 500 virtual machines, he claimed.
SSDs come in two varieties: the kind that can be both read and written to reliably up to 100,000 times, and the less-reliable kind best used for read-only purposes. Frequent writes tend to wear out the latter type's ability to persist data; frequent reads do not. To build mCloud Rack, Damarillo's team had to provide SSD management software that knows the difference and manages data traffic so that it is routed to the correct type of SSD. "Everything is harder to manage. There's a lot more software" than in simpler SSD-invoking designs. But the more reliable solid state devices cost four times as much as the read-only type.
A half rack containing 20 blade servers has 15 TB of storage on 28 SSDs, serving virtual machines with data at near RAM-type speeds, he said. In addition to OpenStack software, it'll have the ZFS file system overlaying the storage so that it can be used as either block or object storage, an advantage for enterprise private cloud implementations. They often cannot make use of cloud-style object storage as readily as the more traditional block storage.
Because the SSD storage serves data faster than mechanical disks, the mCloud blades will enjoy a higher utilization rate, in the range of 60-80%, he said, but have a price tag of $150,000-$175,000. The units will be manufactured by Dell in both half-rack and full-rack sizes.
In the future, the SSD management software will gain the capability to both defragment the drives and spread data writes over the whole capacity of the drive, instead of using and re-using the same portions until they wear out. This feature would extend the life expectancy of a SSD. MorphLab's management software assumes an SSD may fail, so it detects an impending failure and shifts data around to avoid loss, he said.
"The magic we do is in the software managing the SSDs," with a resulting server infrastructure suited to private cloud use and "capable of disrupting Vblocks" and other converged infrastructure offerings, he claimed. Damarillo wanted his mCloud racks to play a disruptive role as lower cost cloud infrastructure than that coming from established hardware vendors.
SSD-based infrastructure is an idea that not everyone is ready for, given solid state's reputation for having a somewhat unpredictable lifespan. But Damarillo thinks maintenance of cloud infrastructure in the future will include regular replacement of SSDs, while maintaining the high performance blades, Arista switches, and Nexenta storage that go into the mCloud racks.
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