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[_] Performance testing, please help!

Tim Wintle timwintle at
Mon Feb 4 17:58:20 GMT 2013

On Mon, 2013-02-04 at 17:39 +0000, Adam Nicholls wrote:


> To clarify: when I say images/css not loading I mean there's a spinning
> wheel next to those files in Firebug. I've done a 'netstat -an' on the
> server and can see the browser has made a connection, although I've noticed
> a few "TIME_WAIT" statuses, not sure what this indicates though or if
> they're related to the files!

That just means the socket is effectively closed, but it's waiting just
in case it needs to re-submit the acknowledgement that the socket will
close (i.e. you can ignore them unless you're maxing out your open

It is possible that there's a networking issue - if you run wireshark on
the client's computer you would be able to track down exactly what's
going on here in more detail, but you'll need a good knowledge of Layer
3 networking (i.e. TCP/UDP).

You may be maxing out allowed sockets on either the client or server,
but you'd need to look at full network logs to find that out.

> Anyone else experienced this kind of behaviour before from a Server or ISP?

Yup - from servers, NICs, switches, datacenters, trans-atlantic

I'm afraid networking is a dark art and I'm not an expert.