Fastest way to download an array of images using multicurl

multidownload.php

<?php
/*
* Fastest way to download an array of images using multicurl
*/
function multi_download(array $urls, $pathToSave)
 {
        $multi_handle = curl_multi_init();
        $file_pointers = [];
        $curl_handles = [];
        if(!file_exists($pathToSave)){
            //create folder
            mkdir( $pathToSave, 0775 );
        }
        
        foreach ($urls as $key => $url) {
            
            $filename = basename($url);
            $file = $pathToSave . '/' . $filename;
            
            $curl_handles[$key] = curl_init($url);
            if(!file_exists($file)) {
                $file_pointers[$key] = fopen($file, "w");
                curl_setopt($curl_handles[$key], CURLOPT_AUTOREFERER, TRUE);
                curl_setopt($curl_handles[$key], CURLOPT_HEADER, 0);
                curl_setopt($curl_handles[$key], CURLOPT_RETURNTRANSFER, 1);
                curl_setopt($curl_handles[$key], CURLOPT_TIMEOUT, 30); //30s
                curl_setopt($curl_handles[$key], CURLOPT_FOLLOWLOCATION, TRUE);  
                curl_setopt($curl_handles[$key], CURLOPT_SSL_VERIFYHOST, FALSE);     
                curl_setopt($curl_handles[$key], CURLOPT_SSL_VERIFYPEER, FALSE);
                curl_setopt($curl_handles[$key], CURLOPT_FILE, $file_pointers[$key]);
                curl_multi_add_handle($multi_handle,$curl_handles[$key]);
            }
        }
        // Download the files
        do {
            curl_multi_exec($multi_handle,$running);
        } while ($running > 0);
        
        // Free up objects
        foreach ($urls as $key => $url) {
            curl_multi_remove_handle($multi_handle, $curl_handles[$key]);
            curl_close($curl_handles[$key]);
            if($file_pointers[$key]){ 
              fclose ($file_pointers[$key]);
            }
        }
        curl_multi_close($multi_handle);
}