Comment by firefly2000
11 hours ago
Do you think it can be done by adjusting GC aggressiveness (or even disabling it for short periods of time) and correlating it with execution time?
11 hours ago
Do you think it can be done by adjusting GC aggressiveness (or even disabling it for short periods of time) and correlating it with execution time?
That is spot on. Effectively disabling GC to establish a baseline is exactly the methodology used in the Blackburn & Hosking paper [1] I referenced.
In general, for a production JVM like HotSpot, the implicit cost comes largely from the barriers (instructions baked directly into the application code). So even if we disable GC cycles, those barriers are still executing.
If we were to remove barriers during execution, maintaining correctness becomes the bottleneck. We would need a way to ensure we don't mark a live (reachable) object as dead the moment we re-enable the collector.
[1] https://dl.acm.org/doi/pdf/10.1145/1029873.1029891