Eugene's observations

For some time I have been encouraging use of solid state disks (SSDs) both in new computers and as a replacement for a failed disk in an old PC. The advantages are clear

• They are fast - maybe 4 times the speed of typical traditional electro-mechanical disks. This gives a noticeable improvement in performance overall, especially when starting the PC or an application
• They use less power than rotating disks
• They are silent
• They generate less heat, requiring less noise and power to remove
• Much more resistant to shock that rotating disks - especially useful in portable computers
• No susceptibility to magnetic surges
• The mean time before failure predictions are superior to traditional disks

There is though, one drawback: they cost more to buy. Although as their use becomes more common this is falling but cost is still a factor affecting many would be purchasers. Enter Hybrid drives. These aim to give a good compromise between the cost of electro-mechanical disks and the benefits of an SSD. They do this by adding a small - perhaps 4GB SSD to a regular disk. The benefits in performance terms are exemplified below.

This compares the time taken to start a fast computer using a traditional 7200 rpm disk, a 10,000 rpm one, a hybrid and a pure SSD. Of course, the mileage will vary with the other components, but the relative advantages of each type of disk are plain.

30-Sep-12 addendum. Defragmentation: Daily for traditional electro mechanical disks, never for SSDs, but what about hybrids ? I recommend defragging hybrids once every 1 - 3 months depending on use. The short term dis-benefits are outweighed by the performance improvements seen after a short time.