In our computer-dependent world, we are always on the lookout for the next “big thing.” Many times it has been a new microprocessor from Intel or AMD. However, in recent years, the microprocessor is often not the limiting factor in computer performance.
Although hard drive memory capacities have increased significantly in recent years, access speeds have remained relatively constant. It is a fundamental question/problem for technology. The hard drive is mechanical, and efforts to improve speed have met with diminishing results.
One technology that competes with the conventional hard drive (HDD) is the solid state drive (SSD). An SSD is not mechanical, it is based on “flash memory”, the same computer chip technology used to store images with your digital camera. An SSD drive was a novelty only 3 years ago, but not anymore.
An SSD can outperform conventional mechanical hard drives because it is 4 times smaller and lighter, is up to 50 times faster, is more reliable because there are no moving parts, produces less heat, and uses less power. SSD memory capacity has improved and 250 gigabyte SSDs are now available. Currently, the drawback is the price.
SSD drives are still more expensive than conventional HDDs. An SSD drive is now around $2 per gigabyte, while an HDD drive is less than $1 per gigabyte. The price of an SSD continues to improve (SSD drives previously sold for over $25 per gigabyte) and with manufacturing volumes expected, the price difference should narrow further.
Flash memory is capable of performing a finite number of rewrites to each memory cell (just like conventional hard drives). Significant improvements in technology have been made in recent years. Also, Intel developed “load leveling”. This technique ensures that all memory cells in the SSD receive a similar workload. Most SSD manufacturers now use comparable techniques. An SSD should last 10 years or more for the average user.
The main reason for the promising future of SSDs is access speed. A fast conventional hard drive has access times of about 5 milliseconds. Sounds fast, but when the microprocessor is capable of millions of instructions per second (MIPS), 5 milliseconds is a bottleneck. SSD can have an access time as low as 100 microseconds (50 times faster).
A major problem when trying to use this SSD speed capability is the potential bottleneck caused by the interface. There are 3 common interfaces used with SSDs today.
The SATA interface is currently the most common interface used for conventional hard drives, but a SATA interface has been limited in total throughput, both send and receive, to approximately 3 Gbps. This may be too slow for SSDs, causing performance hitches. Some SSD drives are capable of throughput of more than 5 Gbps.
Seagate Technology, together with AMD, recently announced the Serial ATA 6 Gbps storage interface, also called SATA Revision 3.0, a next-generation technology that is capable of twice the speed of the fastest SATA interface available today. This technology was demonstrated for conventional hard drives, but it has an obvious application in the SSD market.
SAS (Serial Attached SCSI) is another alternative interface. SAS is a point-to-point technology with at least four channels. Each channel has a throughput capacity of 3 Gbps in each direction (a total of 6 Gbps per channel).
A third alternative is to implement the SSD with a PCI Express interface. A PCI Express interface has unidirectional data paths, one send and one receive, each at 2.5 Gbps for 5 Gbps throughput.
It is possible to maximize the performance advantage of SSD technology with careful selection of the appropriate interface.
Sun Microsystems SSD Backup
Sun Microsystems, a leading manufacturer of engineering workstations (very high performance computers), is unsurprisingly making a strong commitment to SSD technology. Sun can be seen as a benchmark for the PC industry. If Sun supports the technology at the current price, as prices come down, the technology would logically be used by the mainstream PC user. This pattern of adoption has been seen for other new technologies.
Sun has said that it is adding SSD technology to its systems to increase their performance for I/O-intensive applications. Late last year, Sun introduced SSDs to its Amber Road product line. Amber Road is Sun’s new line of data storage systems. Amber Road products sell exceptionally well.
Raymond Austin, group manager for senior product management at Sun, said:
SSD technology helps customers achieve up to 65 times faster response times, up to eight times better performance, and up to 38% less power consumption than servers with traditional spinning hard drives.
An SSD drive will be more tolerant of harsh operating environments and will be more reliable. Computers using SSD drives will experience faster application load times and better overall performance. An SSD can emulate a traditional mechanical hard disk drive (HDD). This makes replacing the traditional HDD with an SSD in your current system less of a hassle. An SSD is probably in your future, the only question is when.