SSD与传统硬盘的比较，大家可以看看。
Abstract
In terms of performance, solid state devices promise
to be superior technology to mechanical disks. This study
investigates performance of several up-to-date high-end consumer
and enterprise Flash solid state devices (SSDs) and relates their
performance to that of mechanical disks. For the purpose of
this evaluation, the IOZone benchmark is run in single-threaded
mode with varying request size and access pattern on an ext3
filesystem mounted on these devices. The price of the measured
devices is then used to allow for comparison of price per
performance. Measurements presented in this study offer an
evaluation of cost-effectiveness of a Flash based SSD storage
solution over a range of workloads.
In particular, for sequential access pattern the SSDs are up to
10 times faster for reads and up to 5 times faster than the disks.
For random reads, the SSDs provide up to 200x performance
advantage. For random writes the SSDs provide up to 135x
performance advantage. After weighting these numbers against
the prices of the tested devices, we can conclude that SSDs
are approaching price per performance of magnetic disks for
sequential access patterns workloads and are superior technology
to magnetic disks for random access patterns.
