Sorry, I do have this evaluation in a spreadsheet somewhere (except against the Tesla K20, K80 wasn't out then), but I just quickly looked up the Mac Pro specs. We do use the D500, so I should have quoted those gflops. There is a benefit to off-the-shelf GPUs, but I don't see it as a make-or-break kind of situation for imgix right now.

I agree that some day in the future, it does seem like it will make sense to bite the bullet and rewrite for Linux. It probably won't solely come down to a cost rationale though, because there are a TON of business risks involved in hitting pause on new features (or doubling team size, or some combination thereof).

Fundamentally I don't believe in doing large projects that have a best case scenario of going unnoticed by your customers (because the external behavior has not changed, unless you screwed up), unless you absolutely have to.

The real reason to migrate to Linux would have to be a combination of at least three things:

  1. Better hardware, in terms of functionality or price/performance
  2. Lower operational overhead
  3. The ability to support features or operations that we can't do any other way

Much more likely, we would adopt a hybrid approach where we still use OS X for certain things and Linux for other things.

Actually, I realized that we were both wrong on the math.

2200 gflop or 3500 gflop are the specs for just one of the Fire Pro cards. Whoops, I was writing a lot of comments that day.

So a Mac Pro with D700 GPUs has 7000 gflop/s and runs $4600 (list), whereas the Tesla K80 has 8740 gflop/s and runs $4900 or so. Since you still need a whole server to go with the K80, I stand by my thinking that it's not a great deal. We also don't need 12GB of VRAM for our use case, so that's a bit of a waste.

In Nvidia's product line, price/gflop is not at its best in their highest end cards. AWS uses the Nvidia GRID K2, for instance. You're paying a lot for the double precision performance in the Teslas, and imaging doesn't need it.

> it will be cheaper to rewrite the software for the render pipeline.

You don't even have to rewrite it, Linux imagemagick + OpenCV can handle the use cases of cropping and sizing trivially. They can keep the rest of the code (device mappings and CDN related I guess) unless that was implemented using ObjectiveC (this is another thing that I would think is crazy)