"I don't know what was wrong" articles like this come up really often with Mongo. My team manages thousands of Mongo nodes and we have issues, but few are direc

"I don't know what was wrong" articles like this come up really often with Mongo. My team manages thousands of Mongo nodes and we have issues, but few are directly due to Mongo. Mongo's documentation could be friendlier to the operator/maintainer, however the tools for debugging Mongo tend to be sufficient (metric counters, various status/state dumps, general Linux tooling). You need to understand databases folks. There is no way around it. "Porting to Postgres" does not replace understanding of database internals and figuring out how to debug bad access patterns and explain why they are bad. Blindly migrating data seems like one of the worst things you could ever do - you're not fixing the problem that you don't understand how databases work. I get it - ain't nobody got time for that - but it will come back and bite you with your new shiny fancy tool too if you aren't careful Anyone who brings up something like master-master hopefully realizes they are talking about a completely different problem now with completely different constraints. Expecting the same access pattern will perform just as well in master-master is wishful thinking - it requires careful design to avoid coordination problems. The meat of the story with databases is: coordination is expensive, distributed coordination is even more expensive