PHP中fwrite与file_put_contents性能测试代码

这里测试的是往文件中写一百万行记录，如果数据量很小，比如1000条左右的记录，可能差距不大

function microtimeFloat() {    list($usec,$sec) = explode(" ", microtime());    return((float)$usec + (float)$sec);}

1.测试file_put_contents

<?php//file_put_contents//by www.jbxue.com$userCount = 1000;$itemCount = 1000;$file = 'ratings.txt';file_exists($file) &&unlink($file);$timeStart = microtimeFloat();for ($i = 0; $i < $userCount; $i++) {    $uid =random(32);    for ($j = 0;$j < $itemCount; $j++) {       $itemId = mt_rand(1, 300000);       $rating = $j == 0 ? 1 : mt_rand(1, 100) / 100;       $line = sprintf("%s,%d,%s\n", $uid, $itemId, $rating);       file_put_contents($file, $line, FILE_APPEND);    }}$timeEnd = microtimeFloat();echo sprintf("Spend time: |%s| second(s)\n", $timeEnd -$timeStart);?>

测试结果:
测试过程中出现了打开文件的错误，而且程序执行完成以后写入的数据不完整，只有999997行，漏了3行。最重要的一点是时间花了307秒多，而用fwrite只花了10秒多的时间，差距还是不小的。
D:\myphp\research>php test2.php
PHP Warning: file_put_contents(ratings.txt): failed to open stream:Permission
denied in D:\myphp\research\test2.php on line 79

Warning: file_put_contents(ratings.txt): failed to open stream:Permission denie
d in D:\myphp\research\test2.php on line 79
Spend time: |307.0586669445|second(s)

...
999994:98xDtLjaeD8MG9ywifegZvRRQzVBZbbw,167670,0.15
999995:98xDtLjaeD8MG9ywifegZvRRQzVBZbbw,234223,0.13
999996:98xDtLjaeD8MG9ywifegZvRRQzVBZbbw,84947,0.79
999997:98xDtLjaeD8MG9ywifegZvRRQzVBZbbw,6489,0.38


2.测试fwrite

<?php//fwrite//by www.jbxue.com$userCount = 1000;$itemCount = 1000;$file = 'ratings.txt';file_exists($file) &&unlink($file);$fp = @fopen($file, 'ab');if (!$fp) die("Open $file failed");$timeStart = microtimeFloat();for ($i = 0; $i < $userCount; $i++) {    $uid =random(32);    for ($j = 0;$j < $itemCount; $j++) {       $itemId = mt_rand(1, 300000);       $rating = $j == 0 ? 1 : mt_rand(1, 100) / 100;       $line = sprintf("%s,%d,%s\n", $uid, $itemId, $rating);       fwrite($fp, $line);       $k++;    }}if ($fp) @fclose($fp);$timeEnd = microtimeFloat();echo sprintf("Spend time: |%s| second(s)\n", $timeEnd -$timeStart);?>

测试结果:
写一百万行记录，10秒左右写完，对于PHP来说，速度算不错了。这是在我的个人电脑上面测试的，如果在生产机上测试，可能速度还要快一些。
D:\myphp\research>php test2.php
Spend time: |10.764221191406|second(s)

用fwrite写入的数据是完整的

999997,QOvcZYFJFlFHjiGyGxAc615kOXdX3Yii,246982,0.03999998,QOvcZYFJFlFHjiGyGxAc615kOXdX3Yii,240160,0.39999999,QOvcZYFJFlFHjiGyGxAc615kOXdX3Yii,46296,0.611000000,QOvcZYFJFlFHjiGyGxAc615kOXdX3Yii,26211,0.14

3.总结
如果要往文件里面写入大量的数据，则推荐用fwrite，不要用file_put_contents。在高并发的请求中也建议用fwrite。