PHP和Apache的随机缓慢下载速度

Question

So my company store all PDF files in Amazon S3 privately. When the user request it our system pull it from Amazon S3 and then serve it to the user with following code:

header("Cache-Control: public");
header("Pragma: public");
header("Expires: 0");
header("Content-Description: File Transfer");
header('Content-Disposition: attachment; filename="'.$fileName.'"');
header('Content-Length: ' . strlen($res->body));
header("Content-type: application/pdf");
header("Content-Transfer-Encoding: binary");
header('Connection: close');
echo $res->body;

$res is the respond returned from Amazon with the content from $res->body;

I see random slow download speed when the user try to download the PDF files, especially when the PDF is large (~5mb) compare to the rest that only having 800kb-1.5mb.

Solution tried: 1) Removing the content-length header doesn't help. 2) Remove EnableSendfile off in httpd.conf doesn't help either.

I also checked the server to make sure it wasn't the workload of the server that's causing this. The speed test of both the server and user's workstation looks good too.

Do anyone of you have any idea what is the reason that's causing this slowness?

Answer 1

It might be that multiple people from your company use the internet. You should do a full scan of the network, but still even then your not alone on the internet, and their "virtual" server environments are shared as well.

Answer 2

from my understanding the issue is that simply takes time to fetch the file from S3 in order to return it to the user.

Make yourself a favor:

1. create a signed url for a short period time
2. redirect the user to such url

dont worry, as creating signed urls doesn't expose any private information that compromises your security (if you do ir correctly)