diff --git a/kernel/mars_aio.c b/kernel/mars_aio.c
index 265e56fe..fcdeb732 100644
--- a/kernel/mars_aio.c
+++ b/kernel/mars_aio.c
@@ -43,7 +43,7 @@
 
 #include "mars_aio.h"
 
-#define MARS_MAX_AIO      1024
+#define MARS_MAX_AIO      512
 #define MARS_MAX_AIO_READ 32
 
 static struct timing_stats timings[3] = {};