LMLPHP后院

PHP 内存泄露重现 include 匿名函数技术

maybe yes 发表于 2022-05-01 10:11

这个坑估计全网没有人踩过,这篇应该是公开出来的第一篇,很多人就算是踩了这个坑,也不一定会触发,即使是触发了,也不一定发现的了。

这个是 include 或者是 require 对于匿名函数的内存泄露大坑。

很多市面上的 PHP 教程都说 include require 相当于把代码复制到那个位置,从这个代码示例验证来看,其实不是这样的!

$i=0;
while (true) {
        if ($i%1000 == 0) {
                echo memory_get_usage()."\n";
                sleep(1);
        }
        $i++;
        $b = 'b';
        $render_func = function($d) use ($b) {
                $u = 1;
                //test3.php $x = function(){};
                require 'test3.php';
        };
        $render_func($i);
}
return;

支付宝篡改行程卡UI院内

maybe yes 发表于 2022-04-23 12:48

支付宝作恶啊,竟然敢篡改行程卡界面,假的也成了真的,真的竟然成了假的!

通过支付宝的 通信大数据行程卡 下面有个 行程卡使用说明,点进去大家都会发现,真正的官网是 xc.caict.ac.cn。

支付宝修改了行程卡的 UI,这样,如果你通过官方渠道去获取了行程卡的截图,发现和支付宝的不一样,字体不一样。因为普通大众只知道支付宝,所以会认为官方的是假的,这样随意篡改官方 UI 的行为真的要严惩。

祸国殃民的 APP!

我有两者的截图,但是懒得放了,大家试一下就知道了,界面的背景颜色略有不同,字体和大小均不相同。

而国内的腐败集团,特别喜欢要求民众截图,这种劳民伤财无意义的行为!渔翁得利啊!反正我大阿里日活是高了。!

How to Increase Number of Open Files Limit in Linux技术

maybe yes 发表于 2022-04-17 17:43

发现这个比较难搞,中文的网页没有一个是对的。

Find Linux Open File Limit
The value is stored in:

# cat /proc/sys/fs/file-max

818354
The number you will see, shows the number of files that a user can have opened per login session. The result might be different depending on your system.

For example on a CentOS server of mine, the limit was set to 818354, while on Ubuntu server that I run at home the default limit was set to 176772.

If you want to see the hard and soft limits, you can use the following commands:

Check Hard Limit in Linux
# ulimit -Hn

4096
Check Soft Limits in Linux
# ulimit -Sn

1024
To see the hard and soft values for different users, you can simply switch user with “su” to the user which limits you want to check.

For example:

# su marin
$ ulimit -Sn

1024
$ ulimit -Hn

4096
How to Check System wide File Descriptors Limits in Linux
If you are running a server, some of your applications may require higher limits for opened file descriptors. A good example for such are MySQL/MariaDB services or Apache web server.

You can increase the limit of opened files in Linux by editing the kernel directive fs.file-max. For that purpose, you can use the sysctl utility.

Sysctl is used to configure kernel parameters at runtime.

For example, to increase open file limit to 500000, you can use the following command as root:

# sysctl -w fs.file-max=500000
You can check the current value for opened files with the following command:

$ cat /proc/sys/fs/file-max
With the above command the changes you have made will only remain active until the next reboot. If you wish to apply them permanently, you will have to edit the following file:

# vi /etc/sysctl.conf
Add the following line:

fs.file-max=500000
Of course, you can change the number per your needs. To verify the changes again use:

# cat /proc/sys/fs/file-max
Users will need to logout and login again for the changes to take effect. If you want to apply the limit immediately, you can use the following command:

# sysctl -p
Set User Level Open File limits in Linux
The above examples, showed how to set global limits, but you may want to apply limits per user basis. For that purpose, as user root, you will need to edit the following file:

# vi /etc/security/limits.conf
If you are a Linux administrator, I suggest you that you become very familiar with that file and what you can do to it. Read all of the comments in it as it provides great flexibility in terms of managing system resources by limiting users/groups on different levels.

The lines that you should add take the following parameters:

<domain>        <type>  <item>  <value>
Here is an example of setting a soft and hard limits for user marin:

## Example hard limit for max opened files
marin        hard nofile 4096
## Example soft limit for max opened files
marin        soft nofile 1024
Final thoughts
This brief article showed you a basic example of how you can check and configure global and user level limits for maximum number of opened files.

While we just scratched the surface, I highly encourage you to have a more detailed look and read regarding /etc/sysctl.conf and /etc/security/limits.conf and learn how to use them. They will be of great help for you one day.

记录一个问题技术

maybe yes 发表于 2022-04-16 17:58

记录一个问题,有没有好的解决方案!

假设 archive.tgz 大小约 2M,里面有 1000 个小文件,其中一个文件名字为 a.txt,我们为了拿到 a.txt,则需要执行下面的命令!

tar zxOf archive.tgz a.txt

现在的问题是,上面的命令存在性能问题,耗时有时候会高达 20s。如何加快这个速度呢?

最好的解决问题的方法,我猜想,因该是不压缩,只打包!

真的乱了院内

maybe yes 发表于 2022-04-12 15:52

真的乱了,你醒悟了吗?据说朋友圈已经很多不显示了,还限地区呢?不知道笼子里的你醒悟了吗?

说多了也无意义,家里有孩子上学的一定深受其害,总而言之,就是社会乱了,教育系统已经够烦了,一天要填多少次表格,一天要接多少次龙,一天要摸排多少次?

现在已经恶心到,阿猫阿狗乱收集信息,地方势力疯狂乱收集信息,这些信息给了谁也不知道,我去,悲催的世界啊!某某日记说的,高科技做起恶来,一点不比瘟疫弱!

如下网站只能微信客户端打开,复制链接出来如下:

http://phxdzht2.jkeqt.com/front/frontm/info.html
http://phxdzht2.jkeqt.com/front/Frontm/index.html?t=22
2022-05-21 21:29:45 1653139785 0.004169