I recently started hosting my own Mastodon instance, but was having a difficult time getting it to run on the low-end Droplet configuration at DigitalOcean. I was happy to run this experiment at $5/mo, but $10/mo was too much for the long term.
I found this section in the Mastodon administration docs that recommends running jemalloc to reduce Mastodon’s memory footprint.
It was easy to do and has allowed me to run on the low-end Droplet from DigitalOcean without running out of memory. I still need to upgrade to the next size when I upgrade Mastodon, but then I can size back down for normal operation.