Last week, while running a workload consisting of 200 different queries, we noticed right away that a CPU imbalance was causing a performance issue. Looking at the first graph, below, you can see right away that one of the three CockroachDB nodes was operating at near 100% CPU. Not ideal.
At the time we installed that cluster, we utilized version 21.1.11 of CockroachDB, which was the most current. Now fast forward in time to November 16 — version 21.2.0 has just been released, with a new feature called Admission Control. From the docs for this new feature, one scenario where Admission Control can help is when