We support configuring the GC thresholds via the gc_thresholds config option, however the default can lead to a lot of GC churn on busier instances. This can easily lead to a) a CPU usage by GC of ~20% and b) multiple multi second GC pauses in quick succession.

Since we manually run the GC we could add limits to ensure we don't run the GC e.g. gen 0 no more than once a second, gen 1 no more than once every 10s and gen 2 no more than once every 30s. This a) enforces that we don't repeatedly do gen2 really frequently and b) stops objects getting promoted to gen2 far too quickly.