[twotwotwo]

There is internal work on a SetMaxHeap API: https://github.com/golang/go/issues/23044 (there's a review of related code at https://groups.google.com/forum/#!topic/golang-codereviews/b... ). It isn't perfect (notably, heap size and process size as seen by the OS are not identical) but seems like a step up from ballast or other workarounds.

In the issue thread Caleb Spare also proposed a minimum heap size so that you get GOGC-ish behavior once your app uses enough RAM, but don't have constant GCs with a tiny heap.

There's definitely a common issue where the GOGC heuristic doesn't take advantage of situations where it can collect less often but still remain in the "don't care" range of memory use. (CloudFlare talked about the same thing making benchmark results weird: https://blog.cloudflare.com/go-dont-collect-my-garbage/ )

And there can definitely be situations where GC'ing a bit more would be worth it to keep a process under an important memory threshold to avoid swapping or OOM kills.

The designers famously don't want too many knobs, but some other ways to convey user priorities to the runtime could certainly save users from some awkward workarounds and fiddling w/the existing knobs.