diff --git a/port/port_posix.h b/port/port_posix.h
index d7cd2659e3c67ed0a954a87383491683336aa5b9..e02224828fd3290e1cc1950dff55b680fe2019d1 100644
--- a/port/port_posix.h
+++ b/port/port_posix.h
@@ -186,7 +186,13 @@ typedef pthread_once_t OnceType;
 extern void InitOnce(OnceType* once, void (*initializer)());
 
 #ifndef CACHE_LINE_SIZE
-#define CACHE_LINE_SIZE 64U
+  #if defined(__s390__)
+    #define CACHE_LINE_SIZE 256U
+  #elif defined(__powerpc__) || defined(__aarch64__)
+    #define CACHE_LINE_SIZE 128U
+  #else
+    #define CACHE_LINE_SIZE 64U
+  #endif
 #endif
 
 #define PREFETCH(addr, rw, locality) __builtin_prefetch(addr, rw, locality)