In my rails app, hosted on the Digitalocean app platform, we're seeing high ram usage and can accommodate only 2 puma workers in a pro instance (1 vCPU, 2 GB Ram). Should I prefer more small instances without any workers as that would be more cost-effective? i.e. if it was heroku, then should I use 2x dyno with more puma workers or multiple 1x dynos?

Is there any inherent advantage to using puma in cluster mode vs threaded only with more instances?