October 23, 2008

Carson Schmidt of Teradata on SSDs

Carson Schmidt is, in essence, Teradata’s VP of product development for everything other than applications and database software. For example, he oversees Teradata’s hardware, storage, and switching technology. So when Teradata Chief Development Officer Scott Gnau didn’t have answers at his fingertips to some questions about SSDs (Solid-State Drives), he bucked me over to Carson. A very interesting discussion about SSDs (and other subjects) ensued.

Highlights included:

Carson is convinced that SSDs are the future for Teradata (a year ago he was merely hopeful).
SSDs use 3 watts of power for the same I/O bandwidth that requires 8 watts on slow disk and 15 watts on faster ones. That illustrates why SSD power savings aren’t huge yet. But the gap will grow with Moore’s Law.
Teradata’s database software is not particularly optimized for the sequential nature of disk access. (Note: The extreme form of that statement would not be true.) Hence, Carson doesn’t foresee major changes when SSDs come into play. Hence, that I/O bandwidth comparison is indeed apples-to-apples.
Carson estimates that the ultimate power savings from SSDs will be 2-5X, not 1-2 orders of magnitude as some predict. However, in saying that he is assuming hybrid systems, which also have spinning disk along with their SSDs. (Note: Teradata Virtual Storage, coming in Release 13.0 in 2009, paves the way for hybrid systems.)
Carson doesn’t yet have enough experience with SSD technology to fully understand its “failure modes.” I.e., he doesn’t yet know exactly what he’ll have to overcome to build highly reliable systems based on SSDs. (While that doesn’t shake his ultimate confidence in the technology, it could be taken as a cautionary note about how soon SSDs will take over.)