I share the experience of parent. My startup ages ago wasn't big enough to have perf issues with mongo, but I certainly experienced data loss (ore wiredtiger).

I share the experience of parent. My startup ages ago wasn't big enough to have perf issues with mongo, but I certainly experienced data loss (ore wiredtiger). A company I worked for (with the most capable team of DevOps I've seen in my career, incidentally) eventually moved from self hosting mongo to atlas, hoping to ease the pain. This was already a few years after wiredtiger came out and fix a lot of issues. Performance problems kept happening and we just started switching to postgres. At my new job, DevOps people keep complaining about our mongo clusters on atlas. It's again, terrible perf and occasional weird issues. We did a disk upgrade and the cluster took 3 days to move all the replica from starting up (and replicating data) to running. During those three days we were running with one less replica and everything was to slow. A complete nightmare. Adding another replica wouldn't have solved anything because it would have taken a day to finish booting. They've been trying to migrate off mongo for years but there is never time, as usual.