While software-defined storage (SDS) captures the attention of the market, enterprise IT professionals know that the hardware still matters. The problem is that while a multitude of SDS solutions have come to market the hardware selection pool is essentially limited to three or four hardware providers. These hardware providers are essentially server builders, not storage builders. Storbyte has recently come out of stealth, promising to bring innovation back to storage hardware.
Why Flash Hardware Matters
Flash storage is fast. Fast enough to expose poorly designed software and hardware architectures. Flash is also a complicated device to write data. It is necessary to manage writes properly to ensure maximum life expectancy and to ensure consistent performance while under load. Since the flash memory controller cannot directly overwrite cells containing data like a hard disk does, it uses a process known as garbage collection, to select the next best block to erase and rewrite the new or updated data. Storage systems that are actually just servers in disguise implement drives as independent units, each of which must take care of its own garbage collection responsibilities.
The key component of flash management is the flash controller. Again, in most storage systems there is one controller per SSD. In even a moderately busy system, the controller can become overloaded with the background garbage collection responsibilities, which impacts the front-end performance experience.
Another challenge is flash density. In spite of the increasing density population of all-flash arrays, few have reached the full potential of the technology. A lesson to learn from ultra-thin laptops is that they use flash memory modules instead of drives and can squeeze a lot of capacity into a very small space. The reason that most flash arrays don’t fully exploit flash density is they don’t use these modules. Again, all-flash arrays are actually servers in disguise and current server design requires installing SSD drives in a hard drive bay, not flash modules.
Storbyte is a hardware first company. They’ve invested in hardware design and architecture to make sure their all-flash array delivers consistent, high performance and maximum flash durability. The Storbyte design provides four memory modules managed by a dedicated master ASIC (Application Specific Integrated Circuit), that Storbyte calls “Hydra”. The ASIC processes the various flash control algorithms and intuitive mathematics. For Hydras with four SSDs, modules are connected to a master Hydra, which provides 16 total flash memory targets. Combined, these 16 targets managed by 5 Hydras, equals one Eco Flash Drive. Striping data across the 16 flash drives spreads out flash management tasks like garbage collection, more effectively and more efficiently. It also increases performance. Storbyte claims a 16X performance increase.
Storbyte installs Eco Flash Drives into one of three storage systems. The first system is the SBS 2:16, which provides 524 Terabytes of raw capacity and up to 2.6PB of storage after data deduplication and compression. The second system is the SBS 4:48 which provides 1.57 Petabytes of raw capacity and up to 7.86 Petabytes after data deduplication and compression and the third system is the SBS 1.4 is a single controller system with dual power and connectivity. It offers 131TB of raw capacity and up to 655TB with dedupe and compression.
The result of running five ASICs on each drive and then putting those drives into a storage system is extreme performance from commodity hardware. Storbyte claims the systems can deliver 900k to 3.2 million IOPS and 8 to 24 Gigabytes of bandwidth via standard configurations.
Storbyte’s design also allows them to deliver true net capacity on flash architectures. The system requires zero over provisioning which means 100% of the flash modules capacity is available. True net capacity will provide Storbyte with a significant price advantage since they are not forced to set aside a portion of flash capacity as their competitors must. One of the other key advantages of the Hydra architecture is the patented algorithms mitigate the impacts of block size. Storbyte stated there is less than a 5% difference between small and large block reads/writes.
Finally, the system also includes a core set of data services. Features include deduplication, compression, high availability clustering, volume management and RAID. While the intent of these features is to get a customer going, the hardware is clearly designed to work with software-defined storage solutions providing those products with a platform to show off their capabilities.
Hardware still matters, especially in flash storage because the media is so fast it can expose weakness in the architecture. Flash also has weaknesses of its own, mostly related to the performance impact of managing writes. Storbyte has invested heavily in working around the write related problems, sheltering users and applications from its effect.