We can give servers more memory, claims Diablo. Well, sort of
Flash substitute for DRAM yet to provoke an emotional response
Diablo Technologies has launched its Memory1 flash substitute for DRAM, which, it claims, gives servers more "memory", enabling one server do the work of ten, saving on power, cooling and rack space, and threatening to slash server sales.
Its Memory1 products are all-flash DDR4 DIMMs developed from its existing MCS (Memory Channel Storage) product which uses DDR3 DIMMs and is licensed to SanDisk for use in its ULLtraDIMM products. SanDisk supplies these to Lenovo, Huawei and Supermicro for use in their servers.
DRAM is expensive, and Diablo is turning flash into slightly slower but cheaper page-accessed memory which it says can be used by system and app software with no change.
Diablo is now mounting its NAND chips directly on DDR4 memory DIMM cards, enabling much larger server "memory", with 4TB 2-socket servers mentioned in its material.
Oddly, it is abandoning the non-volatile characteristic of NAND, it said in its background information material. In the event of a crash or power loss, data will be gone.
It said Memory1 uses the JEDEC NVDIMM-F hardware architecture to expose non-volatile memory (NVM) capacity as system memory. Diablo claims that "by combining the advantages of NVM and DRAM, Memory1 is able to provide DRAM-like application-level performance ... Intelligent algorithms manage communication between DRAM and NVM to optimise system and application performance".
Each flash DIMM module holds up to 256GB of byte-addressable system (flash) memory, four times more than DRAM capacity-wise. Memory speeds of up to 2133MT/s (megatransfers per second) are supported. There is a software component as well as the Memory1 DIMMs. LRDIMMS and RDIMMS are supported as is DIMM interleaving.
There are 64GB, 128GB and 256GB capacity points, with 128 and 256GB product being offered in single and dual rank topologies.
Diablo said Memory1 use requires no changes to a server, apart from a possible UEFI mod, a CPU, the Linux server operating system or applications. It seems to be virtually plug-and-play.
There is a distinct trend emerging of software and hardware storage technology used to move primary data, application working sets, closer to server processors for faster data access than is possible through SAS, SATA or network links like Fibre Channel.
The storage media is solid state and not disk. It is being helped by standard NVMe software drivers for PCIe-connected flash memory cards. Pure Storage and EMC's DSSD are riding this wave with NAND media.
Intel and Micron's 3D XPoint memory is part of this trend, with XPoint memory being used instead of NAND. Diablo's Memory1 is another.