redis和memcache非常像的，都是key,value的方式，將數(shù)據(jù)存放內(nèi)存中。最近在學(xué)習(xí)redis，在網(wǎng)上看了一些這方面的資料，有三種觀點(diǎn)：

1,redis讀寫內(nèi)存比memcache快

2,memcache讀寫內(nèi)存比redis快

3,memcache讀寫內(nèi)存比redis快，但是redis整體性能優(yōu)于memcache

所以我做了一下測(cè)試。關(guān)于redis和memcache的安裝，請(qǐng)參考linux redis 安裝配置, 以及redis php擴(kuò)展

linux memcache 安裝

1，redis的測(cè)試文件

1.<?php  
2.function get_data (){  
3.   mysql_connect("localhost", "root", "") or die("Could not connect: " . mysql_error());  
4.   mysql_select_db("ugc");  
5. 
6.   $result = mysql_query("SELECT task_id FROM ugc_tasks");  
7.   $return = array();  
8.   while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {  
9.      $return[] = $row;  
10.   }  
11. 
12.   mysql_free_result($result);  
13.   return $return;  
14.}  
15. 
16.$redis = new redis();  
17.$redis->connect('127.0.0.1', 6379);  
18. 
19.if ($redis->exists('test')) {  
20.   $value = $redis->get("test");  
21.}else{  
22.   $value = get_data();  
23.   $redis->set('test',json_encode($value));  
24.}  
25. 
26.print_r(json_decode($value));  
27.?> 
<?php
function get_data (){
   mysql_connect("localhost", "root", "") or die("Could not connect: " . mysql_error());
   mysql_select_db("ugc");

   $result = mysql_query("SELECT task_id FROM ugc_tasks");
   $return = array();
   while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
      $return[] = $row;
   }

   mysql_free_result($result);
   return $return;
}

$redis = new redis();
$redis->connect('127.0.0.1', 6379);

if ($redis->exists('test')) {
   $value = $redis->get("test");
}else{
   $value = get_data();
   $redis->set('test',json_encode($value));
}

print_r(json_decode($value));
?>
2，redis的測(cè)試結(jié)果

第一次
root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_redis.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_redis.php
10000 clients, running 30 sec.

Speed=48324 pages/min, 40318471 bytes/sec.
Requests: 22599 susceed, 1563 failed.

telnet 127.0.0.1 6379 telnet登錄一下，把test對(duì)應(yīng)的值清除掉，保重測(cè)試的公平性
del test

第二次
root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_redis.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_redis.php
10000 clients, running 30 sec.

Speed=53570 pages/min, 41217689 bytes/sec.
Requests: 23106 susceed, 3679 failed.

telnet 127.0.0.1 6379
del test

第三次
root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_redis.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_redis.php
10000 clients, running 30 sec.

Speed=49450 pages/min, 39694073 bytes/sec.
Requests: 22301 susceed, 2424 failed.

telnet 127.0.0.1 6379
del test

3,memcache測(cè)試文件

1.<?php  
2.function get_data (){  
3.   mysql_connect("localhost", "root", "") or die("Could not connect: " . mysql_error());  
4.   mysql_select_db("ugc");  
5. 
6.   $result = mysql_query("SELECT task_id FROM ugc_tasks");  
7.   $return = array();  
8.   while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {  
9.       $return[] = $row;  
10.   }  
11. 
12.   mysql_free_result($result);  
13.   return $return;  
14.}  
15. 
16.$mem = new Memcache;  
17.$mem->connect("127.0.0.1",11211) or die ("Could not connect");  
18.$value = $mem->get('test1');  
19.if (emptyempty($value)) {  
20.   $value = json_encode(get_data());  
21.   $mem->set('test1',$value,0, 600);  
22.}  
23. 
24.print_r(json_decode($value));  
25.?> 
<?php
function get_data (){
   mysql_connect("localhost", "root", "") or die("Could not connect: " . mysql_error());
   mysql_select_db("ugc");

   $result = mysql_query("SELECT task_id FROM ugc_tasks");
   $return = array();
   while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
       $return[] = $row;
   }

   mysql_free_result($result);
   return $return;
}

$mem = new Memcache;
$mem->connect("127.0.0.1",11211) or die ("Could not connect");
$value = $mem->get('test1');
if (empty($value)) {
   $value = json_encode(get_data());
   $mem->set('test1',$value,0, 600);
}

print_r(json_decode($value));
?>
4，memcache測(cè)試結(jié)果

第一次

root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_memcache.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_memcache.php
10000 clients, running 30 sec.

Speed=61632 pages/min, 52228667 bytes/sec.
Requests: 29205 susceed, 1611 failed.

telnet 127.0.0.1 11211 telnet登錄一下，把test1對(duì)應(yīng)的值清除掉，保重測(cè)試的公平性
delete test1

第二次

root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_memcache.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_memcache.php
10000 clients, running 30 sec.

Speed=64160 pages/min, 52601449 bytes/sec.
Requests: 29426 susceed, 2654 failed.

telnet 127.0.0.1 11211
delete test1

第三次

root@ubuntu:/home/zhangying/download/webbench-1.5# webbench -c 10000 -t 30 http://localhost/php-redis/test_memcache.php
Webbench - Simple Web Benchmark 1.5
Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.

Benchmarking: GET http://localhost/php-redis/test_memcache.php
10000 clients, running 30 sec.

Speed=65190 pages/min, 52506614 bytes/sec.
Requests: 29348 susceed, 3247 failed.

telnet 127.0.0.1 11211
delete test1

從上面比較結(jié)果，可以看出，memcache比redis快的。redis對(duì)key,value的管理，更靈活。有很多人把redis歸于nosql的范圍，細(xì)細(xì)想，還真是那么一回事。redis還可以把內(nèi)在中的數(shù)據(jù)，放到磁盤中，這一點(diǎn)上，redis更像memcachedb。關(guān)于使用哪一種，看個(gè)人喜好而定了。