Ruby Issue Tracking System

04/09/2026

12:24 PM Ruby Revision c9b70883 (git): Introduce power-of-two size pools

Replace the RVALUE_SLOT_SIZE-multiplier based pool sizes with explicit
power-of-two (and near-power-of-two) slot sizes. On 64-bit this gives
12 heaps (32, 40, 64, 80, 96, 128, 160, 256, 512, 640, 768, 1024)
instead of 5, providing finer ... eightbitraptor (Matt V-H)

12:24 PM Ruby Revision b6658c1e (git): Introduce RVALUE_SIZE GC constant

Add GC::INTERNAL_CONSTANTS[:RVALUE_SIZE] to store the usable size
(excluding debug overhead) of the smallest pool that can hold a standard
RVALUE. eightbitraptor (Matt V-H)

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)