place work-stealing queue indices on different cache lines to avoid f…

…alse-sharing
JuliaLang · Jan 23, 2024 · 735a887 · 735a887
1 parent 5824c73
commit 735a887
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/work-stealing-queue.h b/src/work-stealing-queue.h
@@ -36,7 +36,8 @@ static inline ws_array_t *create_ws_array(size_t capacity, int32_t eltsz) JL_NOT
 
 typedef struct {
     _Atomic(int64_t) top;
-    _Atomic(int64_t) bottom;
+    char _padding[128 - sizeof(int64_t)];
+    _Atomic(int64_t) bottom; // put on a separate cache line. conservatively estimate cache line size as 128 bytes
     _Atomic(ws_array_t *) array;
 } ws_queue_t;