Especially with the Intel X-25 at around $4.50 per GB and DDR2 running at $10 per GB - there just isn't much of a cost savings for completely disparate performance.

When you calculate the price of RAM, consider the slots as well. Putting a TB of RAM in a server requires more than just DIMMs.

But as the paper linked by the article[1] points out, a single server can hold much more data in SSD storage then in onboard RAM.

For ordinary databases, one sweet spot for SSDs is for index tablespaces.

[1] - http://research.microsoft.com/en-us/um/people/antr/ms/ssd.pd...