How to investigate cause of slow server response?

[keyon]

Sometimes after I launch an email campaign, I have visitors complaining that my site won't load (from links in the email). Usually it's a matter of visitors getting the standard "site not available" error message in their browser. In most cases, the site comes back up in a minute or two.

Since all my links are working properly, I'm wondering if my web hosting package isn't robust enough to handle the sudden surge of traffic (which includes people downloading PDFs from my site). Actually, I've noticed this happening to myself when I try to visit sites via other people's email campaigns.

What's the best way to investigate the source of the problem? I'm assuming there's something in my control panel that would tell me if there's a problem.

Thanks!

[avmood]

If you are using a share hosting, then it is possible. Try to load your website from different computers during different times and see if there are any slowness. There is not much you can do but to upgrade your hosting service as most share server are share by hundreds of websites and if some of them running big sql queries, it will slow your website down.

[deepsand]

If you are using a share hosting, then it is possible. Try to load your website from different computers during different times and see if there are any slowness. There is not much you can do but to upgrade your hosting service as most share server are share by hundreds of websites and if some of them running big sql queries, it will slow your website down.

Overly simplistic nonsense.

Sometimes after I launch an email campaign, I have visitors complaining that my site won't load (from links in the email). Usually it's a matter of visitors getting the standard "site not available" error message in their browser. In most cases, the site comes back up in a minute or two.

Since all my links are working properly, I'm wondering if my web hosting package isn't robust enough to handle the sudden surge of traffic (which includes people downloading PDFs from my site). Actually, I've noticed this happening to myself when I try to visit sites via other people's email campaigns.

What's the best way to investigate the source of the problem? I'm assuming there's something in my control panel that would tell me if there's a problem.

A properly working server will never return a 404 Not Found for a Server Busy condition but rather a 5XX, generally a 503 Service Unavailable or, if a proxy server is in use, a 504 Gateway Timeout.

Depending on the browser/version being used, and the user's time-out setting, many 404s are not 404s at all, but a case of the browser not getting a response within the prescribed time, and mis-reporting such as a 404, a common occurrence.

As for your Control Panel, unless it's one that incorporates Server Log data, it's not going to be of much use here.

Step one would be to examine the server logs to determine if the server itself is reporting that 404s are being returned for exiting files; if so, you'll need to contact your host for an explanation and resolution of the problem. Ditto for any 5XX errors.

As for what are actually time-out problems, such are not necessarily the fault of the server, but could be owing to conditions in the particular route that the user's request followed. What you experience is not necessarily what all others experience.

You can investigate the route from your machine(s) to your site's server by doing recursive traceroutes, looking for unusual delays at the various points along the route. You can also try doing the same using various proxies so as to get views from other geographical locations.

If certain users are behind a proxy, are located such that the routes from their machines to your site's server are problematic, or are using browsers that return false 404s, there is nothing that you can do to fix that.