A similar thing also seems to be happening for me when trying to access http://wdjenkins2.wmflabs.org/ci when the proxy works.
Looking at the javascript console during load a handful of things seem to get loaded straight away and everything else sites in pending.
While looking at the access.log of the instance requests seem to come through in bursts to the server.

This ticket needs a better bug summary. :-/

physik wrote:

I was trying the follwing.
I tried wget localhost from the newly created labs-vagrant instance
https://gist.github.com/physikerwelt/da038692e31efef5db1a

Try also
time curl -v http://drmf.beta.wmflabs.org/wiki/Main_Page > out.html
and tailf out.html in another window

You see that the page content up to

<li id="t-print"><a href="/w/index.php?title=Main_Page&amp;printable=yes" rel="alternate" title="Printable version of this page [p]" accesskey="p">Printable version</a></li>
<li id="t-permalink"><a href="/w/index.php?title=Main_Page&amp;oldid=1" title="Permanent link to this revision of the page">Permanent link</a></li>

is delivered in a reasonable time. Afterwareds it takes exactly one minute from the beginning of the request to load the footer of the page.

My time issue is now solved with another bug, but it looks like others are still having issues

If your proxy'd server is a wiki, it could be bug 63338, which added a 60 second delay to every wiki request (index.php, but no load.php or api.php). Gerrit 120958 reduced the timeout from 60 seconds to 0.1 seconds, so if that is your problem then updating core (/srv/mediawiki) to master will help.

This seems fixed to me. Closing ending a new report.