2 files changed, 58 insertions, 12 deletions

diff --git a/gc.c b/gc.c
index 5adb336be8..d2e4e7cbbc 100644
--- a/gc.c
+++ b/gc.c
@@ -2157,34 +2157,70 @@ newobj_init(VALUE klass, VALUE flags, int wb_protected, rb_objspace_t *objspace,
     return obj;
 }
 
+static inline void
+ractor_cache_fill_freelist(rb_objspace_t *objspace, rb_ractor_t *cr, struct heap_page *page)
+{
+    cr->newobj_cache.using_page = page;
+    cr->newobj_cache.freelist = page->freelist;
+    page->free_slots = 0;
+    page->freelist = NULL;
+}
+
 static inline VALUE
 ractor_cached_freeobj(rb_objspace_t *objspace, rb_ractor_t *cr)
 {
+  retry:;
     RVALUE *p = cr->newobj_cache.freelist;
 
-    if (p) {
+    if (LIKELY(p != NULL)) {
         VALUE obj = (VALUE)p;
         cr->newobj_cache.freelist = p->as.free.next;
         asan_unpoison_object(obj, true);
         return obj;
     }
     else {
-        return Qfalse;
+        if (cr->newobj_cache.free_pages) {
+            struct heap_page *page = cr->newobj_cache.free_pages;
+            cr->newobj_cache.free_pages = page->free_next;
+            ractor_cache_fill_freelist(objspace, cr, page);
+            goto retry;
+        }
+        return false;
     }
 }
 
+#define RACTOR_SLOT_CACHE_NUM 512
+
 static struct heap_page *
-heap_next_freepage(rb_objspace_t *objspace, rb_heap_t *heap)
+heap_next_freepages(rb_objspace_t *objspace, rb_heap_t *heap)
 {
     ASSERT_vm_locking();
 
-    struct heap_page *page;
-
+    // find at least 1 page
     while (heap->free_pages == NULL) {
 	heap_prepare(objspace, heap);
     }
-    page = heap->free_pages;
-    heap->free_pages = page->free_next;
+
+    // cache another pages if available
+    struct heap_page *page = heap->free_pages;
+    size_t free_slots = page->free_slots;
+    struct heap_page *p = page;
+
+    int page_cnt = 1;
+
+    while (p->free_next) {
+        if (free_slots >= RACTOR_SLOT_CACHE_NUM) {
+            break;
+        }
+        free_slots += p->free_slots;
+        p = p->free_next;
+        page_cnt++;
+    }
+
+    heap->free_pages = p->free_next;
+    p->free_next = NULL;
+
+    RUBY_DEBUG_LOG("free_slots:%d pages:%d", page->free_next ? (int)free_slots : (int)page->free_slots, page_cnt);
 
     GC_ASSERT(page->free_slots != 0);
     RUBY_DEBUG_LOG("page:%p freelist:%p cnt:%d", page, page->freelist, page->free_slots);
@@ -2199,13 +2235,13 @@ ractor_cache_slots(rb_objspace_t *objspace, rb_ractor_t *cr)
 {
     ASSERT_vm_locking();
     GC_ASSERT(cr->newobj_cache.freelist == NULL);
+    GC_ASSERT(cr->newobj_cache.free_pages == NULL);
 
-    struct heap_page *page = heap_next_freepage(objspace, heap_eden);
+    struct heap_page *page = heap_next_freepages(objspace, heap_eden);
+    struct heap_page *pages = page->free_next;
 
-    cr->newobj_cache.using_page = page;
-    cr->newobj_cache.freelist = page->freelist;
-    page->free_slots = 0;
-    page->freelist = NULL;
+    ractor_cache_fill_freelist(objspace, cr, page);
+    cr->newobj_cache.free_pages = pages;
 
     GC_ASSERT(RB_TYPE_P((VALUE)cr->newobj_cache.freelist, T_NONE));
 }
@@ -5041,8 +5077,17 @@ gc_sweep_start_heap(rb_objspace_t *objspace, rb_heap_t *heap)
             *p = freelist;
         }
 
+#if 0
+        int free_slots = 0; 
+        for (RVALUE *p = freelist; p; p = p->as.free.next) free_slots++;
+        for (struct heap_page *page = r->newobj_cache.free_pages; page;
+             page = page->free_next) free_slots += page->free_slots;
+        fprintf(stderr, "r:%d unused free_slots:%d\n", r->id, free_slots);
+#endif
+
         r->newobj_cache.using_page = NULL;
         r->newobj_cache.freelist = NULL;
+        r->newobj_cache.free_pages = NULL;
     }
 }
 
diff --git a/ractor_core.h b/ractor_core.h
index c97dfcc85f..b7a24231b8 100644
--- a/ractor_core.h
+++ b/ractor_core.h
@@ -137,6 +137,7 @@ struct rb_ractor_struct {
     struct {
         struct RVALUE *freelist;
         struct heap_page *using_page;
+        struct heap_page *free_pages;
     } newobj_cache;
 
     // gc.c rb_objspace_reachable_objects_from