diff --git a/procps/top.c b/procps/top.c
index 62f9421..119c32b 100644
--- a/procps/top.c
+++ b/procps/top.c
@@ -536,7 +536,7 @@ static void parse_meminfo(unsigned long meminfo[MI_MAX])
 	FILE *f;
 	int i;
 
-	memset(meminfo, 0, sizeof(meminfo));
+	memset(meminfo, 0, MI_MAX*sizeof(unsigned long));
 	f = xfopen_for_read("meminfo");
 	while (fgets(buf, sizeof(buf), f) != NULL) {
 		char *c = strchr(buf, ':');