https://github.com/mmtk/mmtk-core/pull/1094 changed the SFT map implementation to SFTDenseMap when vm_space is enabled for correctness reasons. As we know SFTDenseMap performs worse, and this change affects Julia + MMTk performance negatively. We see slowdown up to 15% in GC time for some benchmarks.
https://github.com/mmtk/mmtk-core/pull/1094 changed the SFT map implementation to
SFTDenseMap
whenvm_space
is enabled for correctness reasons. As we knowSFTDenseMap
performs worse, and this change affects Julia + MMTk performance negatively. We see slowdown up to 15% in GC time for some benchmarks.