<p><pre><code> I'd hapily pay $10-20 for a low volume plan and considerably more for high volume
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How much more? The problem is that, while it's easy to run My/PostgreSQL, it's hard to keep them always on, perfect data integrity, etc. On the lowest end, it's going to cost you at the very minimum $50/month to offer this service. You need two slices starting at $20 a piece plus backups which I'm just fudging at $10/mo.<p>So, you say put multiple clients on a 256MB slice? At what point does that become unfair? I wouldn't want my database to have less than 64MB to its name. So, 4 clients per $50 even for small users? That won't hit a $10/mo price point.<p>Yes, you can get more beefy slices like the 15.5GB slice which could accommodate 248 people offering 64MB a piece (you could probably load this one more since the likelihood of users who under use is greater in greater numbers). Still, assuming you have 300 people on the box, that's a cost of $5.33 per user in equipment alone.<p>BUT, you're service is supposed to scale, so you can't really even put the 248 people on the box because you need excess capacity for when a customer says, well, I want more capacity. I mean, are you going to say, "yes, we scale, but we have to take your database offline for half an hour, find a new box for it and then put it back up. and it'll be that way every time you need more juice."<p>It also misses what makes databases tick: RAM and disk. EC2 and slices can do well on the RAM front, but again, once you give someone the RAM, the costs go up huge. In terms of disk, slices are just bad. No one would claim Xen should be used for a good database server because it's not great for disk i/o.<p>Plus, scaling a database isn't usually an issue of knowing a database - it's about knowing queries. So, if you're putting a scaling guarantee in there, you're offering to write people's code for them.<p>The fact is that databases aren't headaches for people getting 10,000 hits per day unless their queries are grossly wrong (which this service wouldn't fix). If you're a big site, you probably want something better than they could offer.<p><i></i>*Oh, and for anyone who wants this service, it already exists with RightScale. Only problem is that it's way out of the quoted price range.