PHP script stops suddenly without any error - php

Question

I have a PHP script that downloads files with direct link from a remote server that I own. Sometimes large files (~500-600 MB) and sometimes small files (~50-100 MB).
Some code from the script:
$links[0]="file_1";
$links[0]="file_2";
$links[0]="file_3";
for($i=0;$i<count($links);$i++){
$file_link=download_file($links[$i]); //this function downloads the file with curl and returns the path to the downloaded file in local server
echo "Download complete";
rename($file_link,"some other_path/..."); //this moves the downloaded file to some other location
echo "Downloaded file moved";
echo "Download complete";
}
My problem is if I download large file and run the script from web browser, it takes upto 5-10 minutes to complete and the script echos upto "Download complete" then it dies completely. I always find that the file that was being downloaded before the script dies is 100% downloaded.
On the other hand if I download small files like 50-100MB from web browser or run the script from command shell this problem does not occur at all and the script completes fully.
I am using my own VPS for this and do not have any time limit in the server. There is no fatal error or memory overload problem.
I also used ssh2_sftp to copy files from the remote server. But same problem when I run from web browser. It always downloads the file, executes the next line and then dies! Very strange!
What should I do to get over this problem?

Answer 1

To make sure you can download larger files, you will have to make sure that there is:
enough memory available for php
the maximum execution time limit is set high enough.
Judging from what you said about ssh2_sftp (i assume you are running it via php) your problem is the 2nd one. Check your error(-logs) to find if that truly is your error. If so you simply increase the maximum execution time in your settings/php.ini and that should fix it.
Note: I would encourage you not to let PHP handle these large files. Call some program (via system() or exec()) that will do the download for you as PHP still has garbage collection issues.