From a78d53518fee4f499ec37bbbc0ff0fcb20af67ea Mon Sep 17 00:00:00 2001
From: Wenchao Hao <haowenchao22@gmail.com>
Date: Tue, 19 Nov 2024 19:56:45 +0800
Subject: [PATCH] add

Signed-off-by: Wenchao Hao <haowenchao22@gmail.com>
---
 test_swap.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 test_swap.c

diff --git a/test_swap.c b/test_swap.c
new file mode 100644
index 0000000..17ffa61
--- /dev/null
+++ b/test_swap.c
@@ -0,0 +1,58 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <openssl/md5.h>
+
+#define SIZE 19*1024*1024
+#define PAGE_SIZE 4096          // 4KB
+#define CHUNK_SIZE 8 * 1024     // 8KB
+
+unsigned long long tv_to_ms(struct timeval tv)
+{
+	return tv.tv_sec * 1000 + tv.tv_usec / 1000;
+}
+
+int main()
+{
+	int i;
+	char *c;
+	unsigned long *p;
+	struct timeval tv_b, tv_e;;
+
+	p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	if (!p) {
+		perror("fail to get memory");
+		exit(-1);
+	}
+
+	c = (unsigned char *)p;
+
+	/* fill data */
+	for (i = 0; i < SIZE / 8; i += 8)
+		*(p + i) = i;
+
+	/* trigger pageout and get time of pageout */
+	gettimeofday(&tv_b, NULL);
+	madvise(p, SIZE, MADV_PAGEOUT);
+	gettimeofday(&tv_e, NULL);
+
+	printf("swp out bandwidth: %ld bytes/ms\n",
+			SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
+
+	/* read to trigger swapin and */
+	gettimeofday(&tv_b, NULL);
+	for (i = 0; i < SIZE; i += PAGE_SIZE)
+		*(c + i) = i;
+	gettimeofday(&tv_e, NULL);
+
+	printf("swp in  bandwidth: %ld bytes/ms\n",
+			SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
+
+	return 0;
+}