PHP CURL内存泄露的解决方法

Posted 2023-04-25

参考技术A php CURL内存泄露的解决方法

　　curl配置平淡无奇，长时间运行发现一个严重问题，内存泄露！不论用单线程和多线程都无法避免！是curl访问https站点的时候有bug！

　　内存泄露可以通过linux的top命令发现，使用php函数memory_get_usage()不会发现。

　　经过反复调试找到解决办法，curl配置添加如下几项解决问题：

　　复制代码 代码如下:

　　[CURLOPT_HTTPPROXYTUNNEL] = true;

　　[CURLOPT_SSL_VERIFYPEER] = false;

　　[CURLOPT_SSL_VERIFYHOST] = false;

　　CURLOPT_HTTPPROXYTUNNEL具体说明stackoverflow上有，直接贴原文：

　　Without CURLOPT_HTTPPROXYTUNNEL

　　Without CURLOPT_HTTPPROXYTUNNEL : You just use the proxy address/port as a destination of your HTTP request. The proxy will read the HTTP headers of your query, forward your request to the destination (with your HTTP headers) and then write the response to you.

　　Example steps :

　　1）HTTP GET / sent to 1.1.1.1 (proxy)

　　2）1.1.1.1 receive request and parse header for getting the final destination of your HTTP request.

　　3）1.1.1.1 forward your query and headers to www.site.com (destination in request headers).

　　4）1.1.1.1 write back to you the response receive from www.site.com

　　With CURLOPT_HTTPPROXYTUNNEL

　　With CURLOPT_HTTPPROXYTUNNEL : You ask the proxy to open a direct binary connection (like HTTPS, called a TCP Tunnel) directly to your destination by doing a CONNECT HTTP request. When the tunnel is ok, the proxy write you back a HTTP/1.1 200 Connection established. When it received your browser start to query the destination directly : The proxy does not parse HTTP headers and theoretically does not read tunnel datas, it just forward it, thats why it is called a tunnel !

　　Example steps :

　　1）HTTP CONNECT sent to 1.1.1.1

　　2）1.1.1.1 receive HTTP CONNECT and get the ip/port of your final destination (header field of HTTP CONNECT).

　　3）1.1.1.1 open a TCP Socket by doing a TCP handshake to your destination 2.22.63.73:80 (ip/port of www.site.com).

　　4）1.1.1.1 Make a tunnel by piping your TCP Socket to the TCP Socket opened to 2.22.63.73:80and then write you back HTTP/1.1 200 Connection established witch means that your client can now make your query throw the TCP Tunnel (TCP datas received will be transmited directly to server and vice versa). ;

内存泄露java.lang.OutOfMemoryError: PermGen space解决方法

PermGen space的全称是Permanent Generation space,是指内存的永久保存区域,
这块内存主要是被JVM存放Class和Meta信息的,Class在被Loader时就会被放到PermGen space中,
它和存放类实例(Instance)的Heap区域不同,GC(Garbage Collection)不会在主程序运行期对
PermGen space进行清理，所以如果你的应用中有很多CLASS的话,就很可能出现PermGen space错误,
这种错误常见在web服务器对JSP进行pre compile的时候。如果你的WEB APP下都用了大量的第三方jar, 其大小
超过了jvm默认的大小(4M)那么就会产生此错误信息了。
解决方法： 手动设置MaxPermSize大小

修改TOMCAT_HOME/bin/catalina.sh
在# OS specific support. $var _must_ be set to either true or false.上面加入以下行：
JAVA_OPTS="-server -XX:PermSize=64M -XX:MaxPermSize=128M"
建议：将相同的第三方jar文件移置到tomcat/shared/lib目录下，这样可以达到减少jar 文档重复占用内存的目的。