Yes, these benchmarks use forced GC calls (i.e. all phases are STW) because it&#x27;s the only (good) way I can think of to make theses tests deterministic (maybe you know of a better way? I&#x27;d definitely be interested).<p>Of course, I don&#x27;t have such calls on production systems; and while concurrent collections greatly reduce the time spent in STW phases, latency spikes are still a very real issue, as I explained here [1].
The monitoring on my production systems leaves absolutly no doubt that those latency spikes are due to garbage collections: once the GC was out of the picture, every thing was flat and fast again.<p>[1] <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10650885" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10650885</a>