对 http 请求的响应来自 Android 应用程序对 PHP 代码的响应太慢时 Z62E0B5B350C9E34D2C19AA8019D

Question

In a Linux server Nginx as web server,

Response to http request from Android application to PHP code with Nginx is too slow

The point is the response from the server is as following:

echo "{mResponse}"

When mResponse is small (you say 500 bytes), there is no problem and the response is too quick
When mResponse is big (you say 200K bytes), there is a problem and the response is too slow

I doubted on echo and searched a lot and found out the echo may be too slow
There were some solutions like chuncking the big data into smaller chuncks (4096) and then echoing
Or ob_start and...

I tested them and finally found out the problem is somewhere else because when I used the following code, the time of echo is ok:

$time_start =  microtime(true);
$this->echobig("@#@{$mCommand}70{$mUserID}{$mResponse}{$mCheckSum}#@#"); 
echo "\nThe first script took: " . ( microtime(true) - $time_start) . " sec";

$time_start =  microtime(true);
ob_start();
$this->echobig("@#@{$mCommand}70{$mUserID}{$mResponse}{$mCheckSum}#@#"); 
ob_end_flush();
echo "\nThe Second script took: " . ( microtime(true) - $time_start) . " sec";

    public function echobig($string)
    {
        $splitString = str_split($string, 4096);
        foreach($splitString as $chunk)
        {
            echo $chunk;
         }
    }

On both above codes (The first and second scripts) the time was near

0.0005 sec

which is ok

But the Android application is receiving the response in 13 seconds
As I said when the response is small, the Android application quickly receives the response (in 2 seconds )

Now I doubt on Nginx settings or PHP settings (may be buffer limits somewhere)
I don't know which parameter is problematic

Answer 1

Sorry, It has nothing to do with Nginx or PHP
The problem is the following code to calculate the check sum of the mentioned big response:

        $cs = 0;
        $content_length = strlen($string);
        for ($i=0; $i < $content_length;$i++)
        {
                $K = mb_substr($string,$i, 1, 'UTF-8');
                $A = mb_convert_encoding(mb_substr($string,$i, 1, 'UTF-8'),"UTF-8");
                $B = $this->mb_ord_WorkAround($A);
                $cs = $cs + $B;                
                
        }