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HomeBackend DevelopmentPHP TutorialDemonstration code that uses cache APC more efficiently than Memcached on the same server_PHP tutorial

复制代码 代码如下:

$memcachehost = 'localhost';
$memcacheport = '11211';
function microtime_float(){
list($usec, $sec) = explode(" ", microtime());
return ((float)$usec + (float)$sec);
}
function runtime($t1){
return number_format((microtime_float() - $t1)*1000, 4).'ms';
}
$starttime = microtime_float();
$cache_time = '30';
echo "init=====".runtime($starttime).'
';

$sql = "SELECT * FROM hx WHERE id = 10006";
$mem_sql_key = md5($sql);

$t1 = microtime_float();
echo "APC_read=====";
$arrs = apc_fetch($mem_sql_key);
echo runtime($t1).'
';

$t1 = microtime_float();
apc_store($mem_sql_key.'_test', $arrs, $cache_time);
echo "APC_write=====";
echo runtime($t1).'
';

$t1 = microtime_float();
$mem = new Memcache;
$mem->connect($memcachehost, $memcacheport);
echo "MEM_connet=====".runtime($t1).'
';

$t1 = microtime_float();
$arrs = $mem->get($mem_sql_key);
echo "MEM_read=====";
echo runtime($t1).'
';
$t1 = microtime_float();
$mem->set($mem_sql_key.'_test',$arrs,0,$cache_time);
echo "MEM_write=====";
echo runtime($t1).'
';
?>

预先把这句SQL的结果在apc和memcached中都缓存了,然后测试读写速度。
在本机windows上结果:
init=====0.0341ms
APC_read=====0.0439ms
APC_write=====0.0920ms
MEM_connet=====11.0571ms
MEM_read=====0.2630ms
MEM_write=====0.2270ms

在服务器上linux上结果:
init=====0.0131ms
APC_read=====0.0520ms
APC_write=====0.0489ms
MEM_connet=====0.0501ms
MEM_read=====0.1030ms
MEM_write=====0.0801ms

当然反复刷新会有不同的值,这里只是取了一个较平均的值。
win下的不具备什么参考性,主要看linux上的结果。
不算connent时间,大概读写的速度apc都比memcached快上一倍左右。算上memcache_connect的时间,也就是快二倍。
APC即可以实现php文件的opcode缓存,也可以实现user cache,实在是个好东西。

所以,如果当网站规模还小的时候,所有功能可以在一台服务器上完成时,那么缓存的方案首选应该就是APC,不用考虑memcached。但如果考虑到网站规模会不断扩大,这点时间的性能差异其实可以忽略不计的,就应该部署memcached了。
另外,跨服务器使用memcached,最好要使用内网。不然的话,受路由的影响,memcached经常会连接超时(超过100ms),而且会凭空多出来两倍的宽带流量。

www.bkjia.comtruehttp://www.bkjia.com/PHPjc/321268.htmlTechArticle复制代码 代码如下: ?php $memcachehost = 'localhost'; $memcacheport = '11211'; function microtime_float(){ list($usec, $sec) = explode(" ", microtime()); return ((float)$use...
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