Need to convert 1000 images in 5 seconds-- what are our options?

Hi, we’re looking for a server architecture that will allow for converting 1000 images in 5 seconds. As a test, we ran some benchmarks using a 48GB (16 core) droplet, using GNU Parallel to run 1,000 image conversions.

Sample command:

ls -1 *.pdf | parallel --eta convert {} {.}.png

Each image takes around 1.0 second to convert, and with 16 cores running at 100% (monitored via htop), we were able to render all 1000 images in about 60 seconds.

We’d like to, someday (as budget allows), get this down to 5 seconds. We obviously need more droplets working in a distributed environment-- we just don’t know where to start. We’d like to stay with DigitalOcean, as we love the simplicity, value and performance.

What sort of server architecture, applications, tools, services, technologies, etc. would you suggest we look into?

Thank you for your help.