Big SSDs are a big deal. And many of them are now flooding onto the market. While 1 TB hard disk drives (HDDs) were major news not so long ago, SSDs are rushing ahead and are about to achieve the 32 TB mark.
There are already plenty of high-capacity SSDs on the market. Here are some of the options.
Samsung Electronics offers a wide range of SSDs. The PM1725, for example is a 6.4 TB SSD that performs at up to 2,000 MB/s on sequential reads and up to 120k IOPS in random read operation. Like most enterprise SSDs, it uses NAND flash memory as the storage media and a controller as the interface with the host system to map bad data blocks, cache read/write data, and conduct error checking and correction (ECC). But Samsung is also pushing the limits of SSD technology with its latest offerings, with the first examples due out this quarter.
“With our 4th generation V-NAND technology, we can provide differentiated values in high capacity, high performance and compact product dimensions,” said Young-Hyun Jun, president of the memory business at Samsung.
V-NAND is said to stack 30 percent more layers of cell arrays vertically compared to its predecessor. That makes it 64-layer triple-level-cell flash. As a result, its single-die density rises to 512 Gb and its IO speed to 800Mbps. The top of the line will be a 32 TB SAS SSD for enterprise storage systems which will hit the market in 2017. 512 V-NAND chips are stacked in 16 layers to form a 1 TB package with 32 of them contained in one 2.5-inch SSD. The company’s roadmap includes a 100 TB SSD by 2020.
Micron’s take on the market is that the emergence of high-capacity SSDs is being driven by the need for enterprises to modernize their legacy IT infrastructure and the requirement for more agility. Frame-based arrays filled with bays of 10K and 15K HDDs are being gradually replaced with solid state storage.
“Organizations are taking the necessary steps to disaggregate their more active application storage from traditional storage networks,” said Scott Shadley, principal technologist, Micron. “They are moving toward a direct attached storage (DAS) approach to enable businesses to more quickly access and leverage data to achieve the agility and insight they need to succeed.”
Micron has been a firm advocate of new interface technologies like NVMe to help systems reach into the high-capacity ranges in drives with speed and efficiency. The Micron 9100 PCIe NVMe SSD, for example, is built to deliver agility and scale for demanding data center workloads. The basic idea is to bring nonvolatile memory as close as possible to the processor, and this is said to be up to 10 times faster when compared to a single enterprise SATA SSD. It offers 3.2TB of storage in both high height, half length (HHHL) and 2.5-inch form factors.
Micron believes the highest-capacity SSDs at the top of the line make sense for many, but not all, applications.
“The switch to SSDs isn’t that much of an initial expense and will actually save more money in the long run for its performance, power consumption and overall space,” said Shadley. “High-capacity SSDs are well designed for cloud services that support content-sharing traffic, such as video and media streaming, as well as active archiving applications where highly sensitive information isn’t being overwritten only.”
But he added that for read-intensive workloads, you need right-sized endurance to provide users with consistency of data throughput to ensure fast delivery of the information being requested for reading, hearing or watching.
“Thanks to the advent of 3D NAND, individual SSDs are reaching the cost-sensitive and capacity thresholds previously owned by HDDs,” said Shadley.
The Western Digital HGST-branded Ultrastar SN100 SSD family is a balance between capacity and performance. It is targeted at cloud, hyperscale and enterprise hyperconverged systems. The Ultrastar SN100 is available in a 2.5-inch or U.2 form factor, and uses the PCIe interface and a NVMe driver to deliver low latency under even heavy loads. It has a capacity of 3.2 TB.
“The Ultrastar SN100 PCIe NVMe SSD particularly shines under mixed read/write workloads (delivering up to 310K IOPS),” said Walter Hinton, director of client and enterprise solutions marketing, Western Digital. “The SN100 is often used by customers with large scale-out databases like MySQL, Cassandra, MongoDB or Hadoop’s HDFS as these databases favor devices inside the server rather than traditional SAN or NAS network-based storage.”
While the SN100 is one of the most densely packaged SSDs on the market, it is not considered by Western Digital to be an HDD replacement. Rather, it is part of a tiered architecture (used by most hyperscale/cloud/telco organizations) for handling the largest amounts of online transactional processing (OLTP) or online analytical processing (OLAP) data possible to gain insights and make decisions rapidly, but with the vast majority of data being stored long term in data lakes or archives.
“For database applications, consider the IOPS-to-GB ratio to choose between large-capacity SSDs versus performance-optimized SSDs or even tiered architectures,” said Hinton. “SSDs are available in a wide range of performance and capacities, often with varying levels of TCO.”