How SanDisk solid state drives are coming to the fore in business and consumer storage. A reseller guide. In association with

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1 How SanDisk solid state drives are coming to the fore in business and consumer storage A reseller guide In association with

2 Solid state drives (SSDs) represent a great sales opportunity as a storage alternative to hard disk drives (HDDs). Instead of using spinning magnetic platters to store data, they write information electronically to transistors on a memory chip and retain information even when power is switched off. The benefits of this relatively new class of device are immediately apparent, both to consumer and business users. This guide explains the technology underpinning SSDs, outlines the benefits and discusses SanDisk s SSD product range. How SanDisk solid state drives are coming to the fore in business and consumer storage 2

3 Reliability SSDs enjoy several advantages over their spinning mechanical counterparts. One is reliability: the lack of moving parts means there is less to go wrong. One of the biggest dangers for HDD users is the dreaded head crash. Hard drive heads float just microns above the surface of a rapidly spinning drive. Although technology has improved over the years, those magnetic heads can still touch the surface of the disk if subjected to a sudden shock, causing data to be corrupted. Because solid-state drives have no heads this does not arise. SSDs are not perfect there could be failures in firmware or integrated circuitry, for example but they are still far more reliable than HDDs. Speed Perhaps the single biggest benefit that SSDs bring is speed. It isn t just HDDs mechanical spinning that makes them slower, it is also the way information is laid out on the device. An HDD must seek the information stored on the drive, moving the head across the surface of the disk until it finds the required sector. It must then wait until the part of the disk containing information passes under the head before it can be read. The problem is compounded by the fact that even a single file s information can often be stored in fragments across different parts of the disk. Reading just one file can involve a long seek time, which can significantly exceed the actual time spent reading from the disk. SSDs, with no moving parts, instead store and read information by sending a charge to a row of electronic cells called a page. Not only is this faster than writing information to a magnetic disk but it also eliminates seek time, speeding up both read and write times. In practice, this reduces data transfer rates, resulting in noticeably faster loading times for applications and files. Even operating systems can load extremely quickly, leading to the kind of instant-on functionality found in modern ultrabooks. Endpoint computers also resume from sleep mode much faster and shut down without cumbersome wait times, making them useful for mobile users who may need to shut down a device for an impromptu meeting. How SanDisk solid state drives are coming to the fore in business and consumer storage 3

4 SSDs are not just for laptop users. They have a special place in the data centre, which is fast adopting them to significantly bolster performance. They are particularly useful for enterprise applications with intensive read/write requirements, including the following. Media Reading and writing audio and video data in particular require high-performance storage technology. Data volumes are large, especially now that much video is high definition. SSDs are able to store and retrieve this information faster than HDDs, which reduces the latency problem when streaming. Web hosting Today s web applications are far more interactive and often query multiple back-end systems to deliver complex datasets to end-users. SSDs can help web hosting companies by providing better performance, for example in fast database access and data caching, used for data that is regularly accessed and needs to be retrieved quickly by web servers. Financial analytics It is difficult to imagine a more data-intensive, performance-dependent application space than financial analytics. These systems need access to vast amounts of data in near real time or real-time windows. Many companies are migrating to in-memory databases, which use vast amounts of DRAM to store large tables in extremely low-latency memory. But this can be prohibitively expensive for all but the biggest financial players. SSDs provide a valuable compromise, offering data read/write times an order of magnitude faster than HDDs at reasonable prices. Manufacturing Information management is a crucial part of the modern manufacturing environment. Regulatory standards and quality control are unavoidable challenges for modern companies and the amount of data that must be stored is increasing exponentially. This data must be retrieved and analysed quickly to cope with rapidly changing supply chains. SSD technology can help to manage vast amounts of data quickly and effectively. How SanDisk solid state drives are coming to the fore in business and consumer storage 4

5 In data centre environments, SSDs represent a valuable chance to reduce operating costs. The modern data centre manager faces a broad set of challenges. The two most important ones are power and space. Companies without the resources to build or lease larger facilities must cram more computing power and storage capacity into the same space. This leads to a greater power draw per square foot, and that in turn generates heat that must be dissipated to keep equipment functioning effectively. SSDs help to mitigate these challenges. Because they don t have to keep a large chunk of metal spinning thousands of times per second their power requirements are far lower than those of the fast hard drives often used in data centres. Secondly, because the equipment is using less power, SSDs minimise the heat generated by storage equipment. This reduces the load on the chillers, which usually consume a third of the average data centre s power budget, further cutting operational expenditure. Chillers that don t have to work as hard are less likely to fail. Every step that a data centre manager makes to reduce power consumption extends the life of the cooling system, which reduces overall capital expenditure in the long run. How SanDisk solid state drives are coming to the fore in business and consumer storage 5

6 There are two types of SSD storage: single-level cell (SLC), and multi-level cell (MLC). The difference lies in how each of them stores information in the microscopic memory cells that make up the drive. SSDs store bits of information in transistors, just as other memory chips do. The difference is that an SSD has to store data even when the power is turned off. To do this, it uses a special on-chip component known as a floating gate transistor. This creates the equivalent of a tiny cage that can hold a charge whether power is running through the chip or not. These floating gate transistors don t just store an on or off charge; they can store multiple voltages, enabling them to hold multiple values. An SLC chip recognises either that a charge is there or that it isn t, effectively giving it either a 1 or a 0. An MLC chip, on the other hand, can recognise the different levels of charge, enabling it to store multiple bits inside a single cell based on the voltage level that it holds. Each of these approaches has advantages and disadvantages. An SLC has a lower storage density because it is storing only one bit per cell. On the other hand, it can often be faster because it is easier to store and read a simple on or off value. SLC chips can also be more reliable because there is less to go wrong when reading and writing simple binary values. Consequently SLC is a popular type of SSD in enterprise-class applications. MLC chips have a higher storage density than SLC ones because they are putting more information in the same physical space. The downside is that they can be slower to operate because the circuitry that reads and writes to the chip has to cope with the nuances of different voltages in an individual cell. There is also potentially more to go wrong because of the more intricate operations involved, and also the gradual degradation of cells over time. How SanDisk solid state drives are coming to the fore in business and consumer storage 6

7 All NAND-based SSD devices suffer from an intrinsic limitation: the media degrades over time. Repeatedly writing and then overwriting information into cells involves erasing all data before writing new information. Each time this happens, the resistance of the floating gate in the transistors changes, increasing the current required to change its state. Over time, it takes increasingly more power and time to write data into a particular cell, eventually rendering it useless for storage. SSD controllers cope with this by using firmware to constantly monitor the state of cells, deciding where to write information so that they all degrade roughly equally over time, avoiding bad spots on the SSD for as long as possible. MLC SSDs degrade faster because of the complexity involved in storing multiple voltages in a single cell. Conversely, the SLC NAND used in enterprise-class drives, while more expensive and offering lower storage density, has a longer life because of the relative simplicity of writing and reading information to the cells. How SanDisk solid state drives are coming to the fore in business and consumer storage 7

8 All SSDs must talk to the host computer using an interface. SanDisk s SSD products use one of three different interface standards. Serial ATA (SATA) This interface uses a controller to connect the drive to the motherboard at a speed of 6Gbps. Serial attached SCSI (SAS) There is little physical difference between this point-to-point communications system and SATA, and it also operates at 6Gbps on SanDisk systems. PCIe Designed for high-performance applications and useful for enterprise computing, this standard operates at far higher speeds than its counterparts because it sits closer to the host system s CPU and memory, thus avoiding controller processing. How SanDisk solid state drives are coming to the fore in business and consumer storage 8

9 SanDisk divides the market for SSDs into two broad areas: consumer and enterprise. These markets subdivide into further categories. Consumer The consumer market focuses on client devices such as laptop computers and ultra books. Although the quality of SanDisk SSDs is high across the board, consumer-grade solutions are more price-conscious than enterprise ones, with an inevitable trade-off in certain performance characteristics. The consumer market includes two further categories. Consumer retail Ultra Plus Available in capacities up to 256GB, the Ultra Plus can read data at up to 530MBps. This SATA-based SSD can be sold as an upgrade to price-conscious hard-drive users. Resellers can position this unit as a relatively inexpensive way to gain dramatic performance increases. Extreme The SanDisk Extreme consumer SSD delivers noticeable benefits to consumers using ultra book, laptop and desktop devices compared with hard drives. Its 510MBps sequential write speed enables applications and operating system data to be stored very quickly, minimising performance bottlenecks. Sequential read speeds of up to 550MBps also enable retrieval of data and streaming media in a smooth, intuitive computing experience. The drive, available in capacities up to 480GB, is well suited to gaming enthusiasts and also those using PCs as media centres, for example. Other benefits include minimal wear and tear, extending the life of the computer, and lower power consumption compared with traditional hard drives, which will appeal to laptop users. They are also quieter and thinner, making mobile computing far more enjoyable. How SanDisk solid state drives are coming to the fore in business and consumer storage 9

10 Enterprise X110 The SanDisk X110 SSD is a 2.5 inch, 6GB second SSD, using the SATA disk interface to communicate with ultra books, notebooks and desktops. This MLC-based NAND device offers high-storage density at competitive prices and is available in 64GB, 128GB, and 256GB configurations. The controller built into the SSD uses three layers of cached memory to optimise performance. Data coming into the drive can be written to a volatile DRAM cache, a medium-performance ncache or the MLC mass storage. The three layers of cached memory are monitored and prioritised to provide optimal performance for applications running on the client device. The unit is also designed to work hand in hand with power management technologies. It uses low-power modes to dynamically adjust the power used by the SSD, enabling mobile client devices to conserve energy while on the move. X210 The X210 business-class client-side SSD is available in capacities of up to 512GB. Like the X110,it also features sequential read times of up to 505Mbps, but can write data sequentially at up to 470MBps. It also features several other capabilities, including support for Native Command Queuing (NCQ). This enables the driver to queue commands from the host machine, giving it tasks to work on if the host becomes occupied with CPU tasks and can t keep up with the drive s lightning-fast I/O capabilities. NCQ allows the operating system to tell the drive which blocks of data can be wiped internally. TRIM increases the performance of SSDs by enabling them to tidy up redundant blocks of data in advance, creating a clean slate for sequentially writing blocks of data in the future. The result is noticeably faster data write times. How SanDisk solid state drives are coming to the fore in business and consumer storage 10

11 SAS Lightning Read-Intensive Some enterprise applications require data to be read from storage far more often than they need to write it. SSD hardware and firmware can be tailored to meet those needs, providing superior read performance. Lightning Read-Intensive SSD units provide 6Gbps read capability in capacities of 400GB, 800GB, and 1.6TB. They are ideal for applications including data indexing, front-end web servers and web applications. They are also ideally suited to streaming media, which are often written only once but read many times. This also makes them appropriate for virtual tape libraries, replacing tape for archiving when fast retrieval is required. Lightning Write-Intensive SanDisk s Lightning Write-Intensive 6Gbps SAS SSDs are a suitable option for applications in which data must be written quickly to disk. Available in capacities of 200GB and 400GB, they serve application workloads such as data warehousing, analytics and database logging. These disks also have a place in high-performance computing applications, where large amounts of data must be written to storage but may not be accessed frequently. Key industries for such applications include oil and gas, where seismological data is processed, life sciences, aerospace and engineering. Lightning Mixed-Use Many enterprise computing applications require a mix of performance across both read and write cycles. In these cases, a carefully crafted combination of optimal firmware and high-quality NAND SSD technology fits the bill. SanDisk s Lightning Mixed-Use SSDs are available in 200-GB, 400GB, and 800GB capacities. They are optimised for application workloads using a 70/30 per cent mix of read and write cycles. These disks offer data read performance ranging from 385MBps to 450Mbps. They can be used for workloads such as online transaction processing for finance, e-commerce and data warehousing, along with and collaboration. They also make great high-speed storage media for virtual desktop integration, enabling customers to run desktop environments from the server, which minimises operational expenditure. How SanDisk solid state drives are coming to the fore in business and consumer storage 11

12 PCIe Lightning SSA Given their proximity to the host CPU, PCIe-based solid-state memory is more than simply a disk; it becomes an application accelerator. The Lightning Solid State Accelerator is designed for both high-end workstations and enterprise data centre applications. Available in 200GB and 400GB configurations, Lightning SSA plugs straight into the PCIe bus inside a workstation or server, avoiding the delay associated with traditional RAID controllers. The customer s core assets, such as frequently accessed database tables to support workload transactions, would go here. These systems can also be used with FlashSoft, SanDisk s data caching software, in enterprise applications. FlashSoft FlashSoft is SanDisk s server acceleration software. It works with solid-state storage technology to make applications perform faster. The software analyses server operating system behaviour to find out which data is accessed most frequently. This hot data is then cached on a solid-state device, speeding up access times and increasing performance. How SanDisk solid state drives are coming to the fore in business and consumer storage 12

13 When discussing SSD memory with customers, it is important to explain the difference between consumer and enterprise SSDs. All SanDisk SSDs are of high quality, but enterprise-grade devices are often faster and have a longer lifespan. In most cases, this is because of the single level cell technology used in the NAND memory. This is faster to read and write, and has a simpler read and write process thanks to the simple binary storage used for each cell, which means there is less to go wrong over time. Enterprise-grade SSDs at the data centre level are also tailored for types of workload such as read- or write-intensive ones. While these differences are crucial and should be emphasised, remember that all SSD drives can deliver demonstrable benefits to the end-user. Performance SSDs can read and write data about 10 times faster than hard drives. Size Space is at a premium in laptop and ultrabook devices and in data centre servers. SSDs require less space to store data. Sound SSDs operate silently and without vibration. Reliability The lack of moving parts in an SSD dramatically increases reliability. Power consumption In both client-side and enterprise server applications power is always at a premium. SSDs decrease power consumption while maintaining storage efficiency. How SanDisk solid state drives are coming to the fore in business and consumer storage 13