diff -urN orig_0102/userspace-rcu-0.10.2/doc/examples/rculfhash/cds_lfht_destroy.c userspace-rcu-0.10.2/doc/examples/rculfhash/cds_lfht_destroy.c
--- orig_0102/userspace-rcu-0.10.2/doc/examples/rculfhash/cds_lfht_destroy.c	2018-12-21 08:44:46.000000000 +0800
+++ userspace-rcu-0.10.2/doc/examples/rculfhash/cds_lfht_destroy.c	2019-07-12 15:11:38.270598030 +0800
@@ -18,7 +18,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
-
+#include <unistd.h>
 #include <urcu.h>		/* RCU flavor */
 #include <urcu/rculfhash.h>	/* RCU Lock-free hash table */
 #include <urcu/compiler.h>	/* For CAA_ARRAY_SIZE */
@@ -43,9 +43,9 @@
 
 int main(int argc, char **argv)
 {
-	int values[] = { -5, 42, 42, 36, 24, };	/* 42 is duplicated */
+	int values[512];	/* 42 is duplicated */
 	struct cds_lfht *ht;	/* Hash table */
-	unsigned int i;
+	unsigned int i,j;
 	int ret = 0;
 	uint32_t seed;
 	struct cds_lfht_iter iter;	/* For iteration on hash table */
@@ -56,8 +56,12 @@
 	 * Each thread need using RCU read-side need to be explicitly
 	 * registered.
 	 */
+        for (i = 0; i< 512;i++) {
+           values[i] = i; 
+        }
 	rcu_register_thread();
 
+        for (j =0;j < 200000; j++) {
 	/* Use time as seed for hash table hashing. */
 	seed = (uint32_t) time(NULL);
 
@@ -98,6 +102,7 @@
 		rcu_read_lock();
 		cds_lfht_add(ht, hash, &node->node);
 		rcu_read_unlock();
+                //usleep(500);
 	}
 
 	/*
@@ -105,33 +110,33 @@
 	 * random order, depending on the hash seed. Iteration needs to
 	 * be performed within RCU read-side critical section.
 	 */
-	printf("hash table content (random order):");
+	//printf("hash table content (random order):");
 	rcu_read_lock();
 	cds_lfht_for_each_entry(ht, &iter, node, node) {
-		printf(" %d", node->value);
+		//printf(" %d", node->value);
 	}
 	rcu_read_unlock();
-	printf("\n");
+	//printf("\n");
 
 
 	/*
 	 * Make sure all hash table nodes are removed before destroying.
 	 */
-	printf("removing all nodes:");
+	//printf("removing all nodes:");
 	rcu_read_lock();
 	cds_lfht_for_each_entry(ht, &iter, node, node) {
 		ht_node = cds_lfht_iter_get_node(&iter);
 		ret = cds_lfht_del(ht, ht_node);
-		printf(" %d", node->value);
+		//printf(" %d", node->value);
 		if (ret) {
 			printf(" (concurrently deleted)");
 		} else {
 			call_rcu(&node->rcu_head, free_node);
 		}
+                //usleep(500);
 	}
 	rcu_read_unlock();
-	printf("\n");
-
+	//printf("current time: %d\n",j);
 	/*
 	 * cds_lfht_destroy() must be called from a very specific
 	 * context: it needs to be called from a registered RCU reader
@@ -143,7 +148,14 @@
 	if (ret) {
 		printf("Destroying hash table failed\n");
 	}
+        if (j%5000 == 0) {
+           printf("repeat %d times\n",j);
+        }
+        }
 end:
+        if (j != 99999) {
+		printf("only repeat %d times\n",j);
+        }
 	rcu_unregister_thread();
 	return ret;
 }
diff -urN orig_0102/userspace-rcu-0.10.2/doc/examples/rculfhash/Makefile.cds_lfht_destroy userspace-rcu-0.10.2/doc/examples/rculfhash/Makefile.cds_lfht_destroy
--- orig_0102/userspace-rcu-0.10.2/doc/examples/rculfhash/Makefile.cds_lfht_destroy	2018-01-24 04:14:53.000000000 +0800
+++ userspace-rcu-0.10.2/doc/examples/rculfhash/Makefile.cds_lfht_destroy	2019-07-04 10:33:38.860003818 +0800
@@ -17,6 +17,10 @@
 DEPS = jhash.h
 OBJECTS = $(EXAMPLE_NAME).o
 BINARY = $(EXAMPLE_NAME)
-LIBS = -lurcu-cds -lurcu
+#LIBS = -lurcu-cds -lurcu
+
+LIBS = -L /usr/lib64/
+LIBS += -lurcu-cds -lurcu-signal
+CFLAGS += -D RCU_SIGNAL
 
 include ../Makefile.examples.template