[Interest] Extremely sluggish browser performance in Qt 5.5

[Till Oliver Knoll]

> Am 23.06.2015 um 03:14 schrieb John C. Turnbull <ozemale at ozemail.com.au>:
> 
> It seems that the "problem" exists in 5.4.2 as well so it's definitely not a
> regression.

Sorry, just a shot into the blue here. Maybe the problem has to do with how Qt interacts with the underlying network stack? IPv6 setup, maybe?

And does the problem also occur on other (Window) machines? A firewall maybe which gets overly "busy" with that "unknown browser"?

What about other Qt networking (example) apps? Wasn't there once a simple FTP example (I guess that's gone though, since QFtp doesn't exist anymore in Qt 5 - or does it?)?

Or that QML "Flickr Image Viewer" that I have in mind? Do those Qt network applications exhibit the same extreme slowness (which would hint at a problem somewhere in QAbstractSocket and friends maybe)?

Are you in a "corporate network"? What if you run the application in another network (preferably on the /same/ computer)? Are you sure the other browsers don't use a (default system) proxy which would bring the network packets "on the fast lane"?


My best bet is a problem with IPv6, the rest above sorted in "increasing esotheric order"...

Cheers,
  Oliver