Write files on the hard disk under a certain amount of concurrency

<?php
 
function write_log($log_content)
{
    $log_file = &#39;/logs/error.log&#39;;
 
    if(is_file($log_file)) {
        // 检测log文件大小，将每个log文件控制在2m以内
        $log_filesize = filesize($log_file);
        $max_size = 2 * 1024 * 1024; // 可以接受的最大的文件大小
        if($log_filesize >= $max_size) {
            $new_log_file = &#39;/logs/error_&#39; . date(&#39;YmdHis&#39;) . &#39;.log&#39;;
            rename($log_file, $new_log_file);
        }
    }
 
    $fp=fopen($log_file,&#39;a+&#39;);
    if($fp){
        $startTime=microtime();
        do{
            // 这个循环可以保证进程在尝试1m后，如果未能锁定文件，则放弃写入日志的操作
            $canWrite=flock($fp,LOCK_EX);
            if(!$canWrite){
                usleep(round(rand(0,100)*1000));
            }
        }while((!$canWrite)&&((microtime()-$startTime)<1000));
        if($canWrite){
            $content = date(&#39;Y-m-d H:i:s&#39;) . &#39; &#39; . $log_content . "\r\n";
            fwrite($fp,$content);
        }
        fclose($fp);
    }
}