diff --git a/user/src/bin/forktest.rs b/user/src/bin/forktest.rs
index fea6967c..a7d523a8 100644
--- a/user/src/bin/forktest.rs
+++ b/user/src/bin/forktest.rs
@@ -6,7 +6,7 @@ extern crate user_lib;
 
 use user_lib::{fork, wait, exit};
 
-const MAX_CHILD: usize = 40;
+const MAX_CHILD: usize = 30;
 
 #[no_mangle]
 pub fn main() -> i32 {
@@ -31,4 +31,4 @@ pub fn main() -> i32 {
     }
     println!("forktest pass.");
     0
-}
\ No newline at end of file
+}