Ruby Issue Tracking System

03/30/2026

11:31 AM Ruby Revision 0875a0f8 (git): Replace heap_init_slots array with single heap_init_bytes target

Replace per-heap GC_HEAP_INIT_SLOTS with a single GC_HEAP_INIT_BYTES
target.
Instead of allocating a fixed 10k slot budget for each heap to grow
into. This PR gives each heap a fixed 2.5Mb heap growth allowance. This
keeps the overall h... eightbitraptor (Matt V-H)

11:31 AM Ruby Revision db1a23fb (git): Remove unused minimum_slots_for_heap function

eightbitraptor (Matt V-H)

11:31 AM Ruby Revision 3fd1be95 (git): Introduce GC.stat_heap(:heap_allocatable_slots)

eightbitraptor (Matt V-H)

03/25/2026

09:11 AM Ruby Revision 58f5d3a9 (git): wip is this still necessary

eightbitraptor (Matt V-H)

03/09/2026

03:09 PM Ruby Revision 208b173c (git): Look up slot sizes for allocations in a table

Also remove BASE_SLOT_SIZE. eightbitraptor (Matt V-H)

03:09 PM Ruby Revision 5001c193 (git): Compress the size_to_heap_idx table

Index on 8 byte chunks instead of individual bytes. This works because
all pool stot sizes are pointer aligned, so all sizes in an 8 byte range
map to the same heap. eightbitraptor (Matt V-H)

03/04/2026

11:02 AM Ruby Revision 4d7f3ba2 (git): [ruby/mmtk] Cargo format

https://github.com/ruby/mmtk/commit/7889da7c0e eightbitraptor (Matt V-H)

11:02 AM Ruby Revision 09262009 (git): [ruby/mmtk] Fix Cargo format issues

https://github.com/ruby/mmtk/commit/26ec9f7f89 eightbitraptor (Matt V-H)

11:02 AM Ruby Revision 3ec9bafe (git): [ruby/mmtk] Flush obj_free buffers before shutdown finalizers

shutdown_call_finalizer reads candidates from the Rust-side
WeakProcessor, but the main ractor's C-side buffer may not
have been flushed yet (ractor_cache_free runs later). Flush
all remaining buffers before reading candidates.
https://... eightbitraptor (Matt V-H)

11:02 AM Ruby Revision 45dabe33 (git): [ruby/mmtk] Distribute batch candidates across parallel buckets

Instead of sending all 128 buffered objects to one bucket,
round-robin distribute them across all worker buckets so
parallel obj_free work stays balanced.
https://github.com/ruby/mmtk/commit/e1f926cd21 eightbitraptor (Matt V-H)