[nomilk]

For anyone interested, here's the result: https://imgur.com/a/c62gjKQ (the red vertical line is the point from which jemalloc was used).

It looks like memory usage did indeed go down, and critical errors fell by about 84%.

[nomilk]

For completeness, here are the metrics a full 24 hours after the change: https://imgur.com/a/lbdzFvN