per-ractor object allocation

Now object allocation requires VM global lock to synchronize objspace.
However, of course, it introduces huge overhead.
This patch caches some slots (in a page) by each ractor and use cached
slots for object allocation. If there is no cached slots, acquire the global lock
and get new cached slots, or start GC (marking or lazy sweeping).

1 files changed, 5 insertions, 0 deletions

diff --git a/ractor_core.h b/ractor_core.h
index 9f87f15e55..3f367ad559 100644
--- a/ractor_core.h
+++ b/ractor_core.h
@@ -133,6 +133,11 @@ struct rb_ractor_struct {
     VALUE verbose;
     VALUE debug;
 
+    struct {
+        struct RVALUE *freelist;
+        struct heap_page *using_page;
+    } newobj_cache;
+
     // gc.c rb_objspace_reachable_objects_from
     struct gc_mark_func_data_struct {
         void *data;