Ruby Issue Tracking System

05/08/2026

03:13 PM Ruby Revision 06caa59c (git): [ruby/mmtk] Introduce support for ractor_belonging.

This is a debug mode in Ruby where an extra word is used after each
object to store the address of the Ractor that owns the object, used for
debug purposes only.
While we're working on Ractors, we also need to be able to test with
MMTk ... eightbitraptor (Matt V-H)

03:13 PM Ruby Revision 33744d25 (git): [ruby/mmtk] Remove unnecessary null check.

the only caller of this unconditionally constructs a binding options
object now, So actually this is dead code
https://github.com/ruby/mmtk/commit/d832004e89 eightbitraptor (Matt V-H)

04/09/2026

12:24 PM Ruby Revision aa5f1922 (git): Update tests for new pool layout

eightbitraptor (Matt V-H)

12:24 PM Ruby Revision 5c968c50 (git): Cache has_sweeping_pages as a bitfield

eightbitraptor (Matt V-H)

12:24 PM Ruby Revision a8009c98 (git): Allow flex in heap growth threshold

Add a 7/8 multiplier to the min_free_slots checks in
gc_sweep_finish_heap and gc_marks_finish, allowing heaps to be up to
~12.5% below the free slots target without triggering a major GC or
forced growth.
With 12 heaps instead of 5, eac... eightbitraptor (Matt V-H)

12:24 PM Ruby Revision 80e3a8d2 (git): Fix zjit hir tests

eightbitraptor (Matt V-H)

12:24 PM Ruby Revision 2fd891f2 (git): Use the pre-processor to generate slot sizes and reciprocals

eightbitraptor (Matt V-H)

12:24 PM Ruby Revision 5381f0fa (git): Replace sweeping_heaps map with a counter

We implemented some bit twiddling logic with an unsigned int to have a
neat way of tracking which heaps were currently sweeping, but we
actually don't need to care which heap is sweeping right now, just
whether some are or not, so we can... eightbitraptor (Matt V-H)

12:24 PM Ruby Revision 3c28bb53 (git): Make it obvious that field count guard is for debug

This is because when `RVALUE_OVERHEAD` is positive, ie. when
`RACTOR_CHECK_MODE` is enabled and we need to store the pointer to the
owning ractor, we need to make sure there is enough space to store it.
With the previous size pools the ... eightbitraptor (Matt V-H)

12:24 PM Ruby Revision c9197780 (git): Remove extra sentinel from shape capacities

This isn't a 0 terminated list anymore because we iterate over
heaps_count directly. So we don't need to allocate an extra byte for the
sentinel eightbitraptor (Matt V-H)