Ruby Issue Tracking System

11/20/2025

11:10 PM Ruby Revision 3ec44a99 (git): Add a Ractor test case that causes MMTk to deadlock

This was a test case for Ractors discovered that causes MMTk to deadlock.
There is a fix for it in https://github.com/ruby/mmtk/pull/49. peterzhu2118 (Peter Zhu)

11:10 PM Ruby Revision e15b4e1c (git): Bump default compiler to clang-20 in CI

clang-18 has a bug that causes the latest Ractor btest to crash. peterzhu2118 (Peter Zhu)

10:30 PM Ruby Revision 24473808 (git): Run rb_gc_before_fork after before_exec

before_exec stops the timer thread, which requires locking the Ractor
scheduler lock. This may deadlock if rb_gc_before_fork locks the VM. peterzhu2118 (Peter Zhu)

11/19/2025

11:25 PM Ruby Feature #20408 (Closed): Add heap_live_slots to GC.stat_heap

Applied in changeset commit:git|fa02d7a01f5e7516de8eb3c7f92ec75c50c06e3f.
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Implement heap_live_slots in GC.stat_heap
[Feature #20408] peterzhu2118 (Peter Zhu)

11:25 PM Ruby Revision fa02d7a0 (git): Implement heap_live_slots in GC.stat_heap

[Feature #20408] peterzhu2118 (Peter Zhu)

11:25 PM Ruby Revision 83bf0542 (git): Implement heap_free_slots in GC.stat_heap

[Feature #20408] peterzhu2118 (Peter Zhu)

11:25 PM Ruby Revision f5f69d41 (git): Implement heap_final_slots in GC.stat_heap

[Feature #20408] peterzhu2118 (Peter Zhu)

02:08 AM Ruby Revision 69b1c567 (git): [ruby/mmtk] Add VM barrier in rb_gc_impl_before_fork

We need the VM barrier in rb_gc_impl_before_fork to stop the other Ractors
because otherwise they could be allocating objects in the fast path which
could be calling mmtk_add_obj_free_candidate. Since mmtk_add_obj_free_candidate
acquires... peterzhu2118 (Peter Zhu)

02:08 AM Ruby Revision f040b94c (git): [ruby/mmtk] Ensure not blocking for GC in rb_gc_impl_before_fork

In rb_gc_impl_before_fork, it locks the VM and barriers all the Ractors
before calling mmtk_before_fork. However, since rb_mmtk_block_for_gc is
a barrier point, one or more Ractors could be paused there. However,
mmtk_before_fork is not ... peterzhu2118 (Peter Zhu)

11/18/2025

02:32 AM Ruby Revision 0ce6eed7 (git): Unskip test_alternative_pattern_nested for MMTk

peterzhu2118 (Peter Zhu)