diff --color -ruN filebench/config.h modify/config.h
--- filebench/config.h	2022-05-10 11:24:44.393676003 +0800
+++ modify/config.h	2022-05-10 11:15:23.769794727 +0800
@@ -295,6 +295,7 @@
 
 /* Define if you have SYSV sems */
 #define HAVE_SYSV_SEM 1
+#undef HAVE_SYSV_SEM
 
 /* Define to 1 if you have the <sys/dir.h> header file, and it defines `DIR'.
    */
diff --color -ruN filebench/ipc.c modify/ipc.c
--- filebench/ipc.c	2022-05-10 11:24:44.393676003 +0800
+++ modify/ipc.c	2022-05-10 11:16:06.768145518 +0800
@@ -400,21 +400,22 @@
 int
 ipc_attach(void *shmaddr, char *shmpath)
 {
-	int shmfd;
+	// int shmfd;
 
-	if ((shmfd = open(shmpath, O_RDWR)) < 0) {
-		filebench_log(LOG_FATAL, "Could not open shared memory "
-			      "file %s: %s", shmpath, strerror(errno));
-		return (-1);
-	}
+	// if ((shmfd = open(shmpath, O_RDWR)) < 0) {
+	// 	filebench_log(LOG_FATAL, "Could not open shared memory "
+	// 		      "file %s: %s", shmpath, strerror(errno));
+	// 	return (-1);
+	// }
 
-	if ((filebench_shm = (filebench_shm_t *)mmap(shmaddr,
-	    sizeof (filebench_shm_t), PROT_READ | PROT_WRITE,
-	    MAP_SHARED | MAP_FIXED, shmfd, 0)) == MAP_FAILED) {
-		filebench_log(LOG_FATAL, "Could not mmap the shared "
-		"memory file: %s", strerror(errno));
-		return (-1);
-	}
+	// if ((filebench_shm = (filebench_shm_t *)mmap(shmaddr,
+	//     sizeof (filebench_shm_t), PROT_READ | PROT_WRITE,
+	//     MAP_SHARED | MAP_FIXED, shmfd, 0)) == MAP_FAILED) {
+	// 	filebench_log(LOG_FATAL, "Could not mmap the shared "
+	// 	"memory file: %s", strerror(errno));
+	// 	return (-1);
+	// }
+	filebench_shm = (filebench_shm_t *)shmaddr;
 
 	if (filebench_shm != shmaddr) {
 		filebench_log(LOG_FATAL, "Could not mmap the shared "
diff --color -ruN filebench/procflow.c modify/procflow.c
--- filebench/procflow.c	2022-05-10 11:24:44.393676003 +0800
+++ modify/procflow.c	2022-05-10 11:16:35.772217279 +0800
@@ -90,7 +90,8 @@
 		return (-1);
 	}
 #else
-	if ((pid = fork()) < 0) {
+	// if ((pid = fork()) < 0) {
+	if ((pid = vfork()) < 0) {
 		filebench_log(LOG_ERROR,
 		    "procflow_createproc fork failed: %s",
 		    strerror(errno));