diff --git a/src/system_info.c b/src/system_info.c
index 33cea25..6e3f4a2 100644
--- a/src/system_info.c
+++ b/src/system_info.c
@@ -62,7 +62,7 @@ int get_sys_total_mem_size(int64_t *mem_size)
    size_t len;
 
    mib[0] = CTL_HW;
-   mib[1] = HW_PHYSMEM;
+   mib[1] = HW_MEMSIZE;
    len = sizeof(*mem_size);
    if (sysctl(mib, 2, mem_size, &len, NULL, 0) != 0)
    {