Swap memory

rubys · November 3, 2022, 1:00am

FYI, if people run fly launch on a Rails app these days, they get the following:

superfly/flyctl/blob/72736560d1a4119317dc18bb8913ab9a4d4d755b/scanner/templates/rails/standard/lib/tasks/fly.rake#L24-L36


      
          # optional SWAPFILE task:
          #  - adjust fallocate size as needed
          #  - performance critical applications should scale memory to the
          #    point where swap is rarely used.  'fly scale help' for details.
          #  - disable by removing dependency on the :server task, thus:
          #        task :server do
          task :swapfile do
            sh 'fallocate -l 512M /swapfile'
            sh 'chmod 0600 /swapfile'
            sh 'mkswap /swapfile'
            sh 'echo 10 > /proc/sys/vm/swappiness'
            sh 'swapon /swapfile'
          end

In other words, no formula, just a fixed size. One that can be tailored.