Increase in the 99th percentile of SQL timings since the deploy of 10.5.2

Since 10.5.2 has been deployed we're seeing an increase in the 99th percentile of SQL timings:

Screenshot_from_2018-02-28_14-24-42

Here we can see that since 10.5.2 our p99 has almost doubled in the worst case. We need to figure out what caused this and resolve it ASAP.