Agenda is waiting for available socket

[Craig Russell <cr...@oracle.com>]

tl;dr Does Whimsy Agenda Tool keep sockets open to the server after displaying the page?

I finally started using Chrome and after opening several tabs with agenda pages, I opened another and got this message about “Waiting for available socket…”

So I looked on the internet and found this: http://stackoverflow.com/questions/23679968/chrome-hangs-after-certain-amount-of-data-transfered-waiting-for-available-soc

It looks like Chrome only allows six connections to the same server simultaneously. So my question is: Why does whimsy agenda keep sockets open to the whimsy server after displaying the page? 

That would explain a number of issues that I’ve been having. Perhaps Safari has a similar limit but doesn’t tell you about it.

“Here are the maximum number of HTTP connections which you can make with a Chrome browser:

	• The maximum number of connections per proxy is 32 connections. This can be changed in Policy List.
	• Maximum per Host: 6 connections.

This is likely hardcoded in the source code of the web browser, so you can't change it.
	• Total 256 HTTP connections pooled per browser.
Source: Enterprise networking for Chrome devices ( https://support.google.com/chrome/a/answer/3339263?hl=en )”

I verified that I did have six tabs open to the agenda (various tabs) and when I closed one of them, the seventh tab became responsive again.


Craig L Russell
Secretary, Apache Software Foundation
clr@apache.org http://db.apache.org/jdo

Re: Agenda is waiting for available socket

[Sam Ruby <ru...@intertwingly.net>]

On Thu, Jul 21, 2016 at 3:57 PM, Craig Russell <cr...@oracle.com> wrote:
> tl;dr Does Whimsy Agenda Tool keep sockets open to the server after displaying the page?

Yes, but the intent is to only have one socket per browser, not one
per page.  See the comments in this file:

https://github.com/apache/whimsy/blob/master/www/board/agenda/views/models/events.js.rb

If you open your javascript console, the first tab should say
something like "Events id: 1469131634541.1768" followed by "Events:
Assuming the role of master". Subsequent tabs should say something
like "Events.master: 1469131634541.1768" where the number matches the
master.  If you see something different, there is a problem.

I'd love to replace Server Side Events with Web Sockets, but Web
Sockets don't appear to be supported by Apache HTTPD, and I'm not
particularly enthusiastic about switching to nginx.

I'd love to replace localStorage with Service Workers, but Service
Workers is only supported by Firefox and Chrome at the moment.  It is
in active development for Microsoft Edge.  There is no signs of
progress with Safari.

- Sam Ruby

> I finally started using Chrome and after opening several tabs with agenda pages, I opened another and got this message about “Waiting for available socket…”
>
> So I looked on the internet and found this: http://stackoverflow.com/questions/23679968/chrome-hangs-after-certain-amount-of-data-transfered-waiting-for-available-soc
>
> It looks like Chrome only allows six connections to the same server simultaneously. So my question is: Why does whimsy agenda keep sockets open to the whimsy server after displaying the page?
>
> That would explain a number of issues that I’ve been having. Perhaps Safari has a similar limit but doesn’t tell you about it.
>
> “Here are the maximum number of HTTP connections which you can make with a Chrome browser:
>
>         • The maximum number of connections per proxy is 32 connections. This can be changed in Policy List.
>         • Maximum per Host: 6 connections.
>
> This is likely hardcoded in the source code of the web browser, so you can't change it.
>         • Total 256 HTTP connections pooled per browser.
> Source: Enterprise networking for Chrome devices ( https://support.google.com/chrome/a/answer/3339263?hl=en )”
>
> I verified that I did have six tabs open to the agenda (various tabs) and when I closed one of them, the seventh tab became responsive again.
>
>
> Craig L Russell
> Secretary, Apache Software Foundation
> clr@apache.org http://db.apache.org/jdo
>