PHP, search and delete files from directory - performance

Question

Hi,

I want to delete cache files in a directory, the directory can contain up to 50.000 files. I currently I use this function.

// Deletes all files in $type directory that start with $start

    function clearCache($type,$start)
        {
        $open = opendir($GLOBALS['DOC_ROOT']."/cache/".$type."/");
        while( ($file = readdir($open)) !== false ) 
            {
            if ( strpos($file, $start)!==false ) 
                {
                unlink($GLOBALS['DOC_ROOT']."/cache/".$type."/".$file);
                }
            }
        closedir($open);        
        }

This works fine and it is fast, but is there any faster way to do this? (scan_dir seems to be slow). I can move the cache to memory obviously.

Thanks, hamlet

Answer 1

You may want to look into the glob function, as it may be even faster... it depends on the C library's glob command to do its work.

I haven't tested this, but I think this would work::

foreach (glob("$GLOBALS['DOC_ROOT']."/cache/".$type."/".$start) as $file) {
    unlink($GLOBALS['DOC_ROOT']."/cache/".$type."/".$file);
}

Edit: I'm not sure if $file would be just the filename or the entire path. glob's documentation implies just the filename.

Answer 2

Either glob as suggested before or, if you can be certain there won't be malicious input, by issueing directly to the system via exec(sprintf('rm %s/sess*', realpath($path)));, which should be fastest.