On Wed, Jan 22, 2014 at 10:18:45AM -0200, Alex Garz?o wrote: > Hello, > > Ticket: https://issues.apache.org/jira/browse/TS-2520. > > I am a newbie in ATS, but I would like to contribute. Can I implement > a patch to solve this?
Did this ever go anywhere? I'm still interested in such, but as far as I can tell Chrome is sitll sending POST requests that way which will sometimes end up with duplicate requests. I don't know what I thought before, but now I think it's okay to accept even with Chrome's bug-- Chrome doesn't enable by default, and it's not the servers responsibility to deal with buggy client. Getting the connecting out using TFO should definitely be done right though. And I imagine that's where it will get complicated. I should have some spare time in a week or two, so if no-one else wants to try adding support for accepting TFO connections then I should be able to. I imagine it's going to take me quite a long time to get orientated enough to add outbound support though. The other outbound issue is that if you have existing connections you don't want to risk opening a TFO connection to somewhere that may or may not have TFO support, and instead want to reuse an existing connection. As far as performance improvements go - Chrome is already preconnecting. And that preconnecting will only get as far as a proxy server - so if the proxy preconnected too that would give benefit to more users. Although if not careful and preconnecting too much could create a DOS vector - so it'd make sense to err on the side of caution. In a lot of cases even using TFO for POST requests is probably fine - a user can click on POST twice, to duplicate a request, and both normally clients, and proxy to web server connections don't usually have packet loss. (downstream packet loss tends to be more common on cable/adsl networks, and upstream usually has bufferbloat instead, proxies usually have stable connections to web servers, and in high load cases are more likely to congesting down stream than upstream). So if you have a proxy server on the same local network as a server, it's probably safe to accept non TFO connections to the proxy, then do TFO from proxy to web server. Unfortunately web server support still isn't common. I've only tested with modified lighttpd, but afaik none of the web servers have native support yet. Ben.
