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During the first European Tech Field Day Extra (at VMworld EU in Barcelona) one of the companies with the more technical presentation was Diablo Technologies. This company was founded in 2003 and they’re working on Memory Channel Storage (MCS) which is a very high performance host flash solution.
There where Jerome McFarland (Principal Product Marketer, Diablo Technologies), Daniel Beveridge (Senior End User Computing Architect, VMware), Ricky Trigalo (Director Virtualization Solution Architecture, Diablo Technologies) to explain this kind of solution and how apply in virtualized environments.
Currently Diablo Technologies collaborates with some OEM manufacturers (IBM, SuperMicro, SANDISK) to integrate their technology with SSD chips into the newest hardware and, of course, they also work closely with VMware to integrate their solution in vSphere stack.
In the first part Jerome McFarland introduces Diablo memory channel storage and discusses the benefits of moving flash from SSD to PCIe to memory channel.
This kind of solution is really a high performance technology: traditional host flash are connected to the SAS bus (SSD in hard disk form factor) or through the PCIe bus (SSD on cards). But with the MCS solution the flash are just DIMMs connected directly to the CPU using really fast channels and also by benefit of the NUMA topology and proximity.
Carbon1 is the first commercialized MCS RDK that enables NAND flash to direct interface on memory channel. Considering that this kind of DIMM (using DDR3 interface) are not standard RAM DIMM, you need new generation of motherboard with a specific BIOS that can support this kind of device (some specific configuration are needed, like avoid the initial check of this memory, put this device in the ACPI table and reserve the required space). It is totally self-contained, powered by the standard memory interface and does not require any external connectors (so its really seems just a RAM DIMM).
After that, with the right device drivers, you will have a “traditional” block storage like in other SSD solution, with the big difference of a really low (and predictable) latency and high performance on dedicated channel (depending on the number of DIMMs there could be a multiplexing in the CPU channels, but remain still a high performance).
The overall architecture is not so different like all the other block storage DAS connected (the really big difference is where it is connected).
This kind of solution cloud become interesting also in scenario di flash tiering stategy:
- tier1 could be on DIMM Flash
- tier2 could be on SSD MLC o TLC
In the second part Ricky Trigalo and Daniel Beveridge describe more detail on the MCS integration in VMware vSphere and present the impact of memory channel storage on VDI acceleration. The VMware scenario is one of the possible scenario, but not necessary the only one.
More DIMM could be aggregated (at BIOS level) in a single RAID0 unit, so that you can see (at hypervisor level) as a single SSD drive (considering for example PernixData limit for the small bundle, or also VSAN limit). In the future will be possible implement also a RAID1 to provide more resiliency across the flash on single host. Of course to provide more resiliency across more hosts you need third part solution (like PernixData or VSAN).
VDI is probably one of most interesting user cases (and was used as an example). This kind of storage can really solve the I/O response time issue presenting a thin stack:
In VDI environments, baybe you don’t really need of milion IOPS in VDI, but good and quality storage and combining this kind of storage solution with VSAN and Horizon View make this solution really interesting.
Price could be a possible limit, but MCS memory does not necessary costs so much compared to PCI SSD making this kind of solution also affortable.
- Tech Field Day extra at VMworld EU
- SSD Storage Closer to CPU – That’s Memory Channel Storage by Diablo Technologies for Next Gen VSAN
- Diablo Technologies at SFD5 and Updates
Disclaimer: I’ve been invited to this event by Gestalt IT, but I’m not compensated for my time and I’m not obliged to blog. Furthermore, the content is not reviewed, approved or published by any other person than me.