Memory leaks in IE/Chrome when use SignalR longPolling

[Xiaohongt]

I have run sample message loops which does both send and receive messages for about 12 hours on IE and Chrome using longPolling transport, the results for process memory data Working Set –Private show that there are memory leaks.

BTW, the run for directly using XMLHttpRequest to send message /post and poll/get to signalr ( just like longPolling ) in infinite loops but without SignalR js run for over 10 hours on Chrome, doesn’t show memory leaks.

[pfletcher]

More issues from the reporting user:

Hi Patrick, Thanks again for your timely response.

To reiterate, I don't believe that the memory leak is limited to just Chrome/LongPolling.

My observations were that it also occurred for all the following combinations as well

IE 10/'foreverFrame' and IE 10/'longPolling' and

FireFox 27/'serverSentEvents' and FireFox 27/'longPolling'

I have numerous Memory Resource Monitor screen shots to support my claims should you need them.

• Michael

[pfletcher]

Continued info:
I had also observed from the Resource Monitor Memory page that in addition to the
Browser process memory leak that the associated 'w3wp.exe' process was also leaking
memory.
Here is a summary of the steps that I had taken to isolate this issue.

1. I deployed the SignalR.StockTicker sample application to the 'ASP.NET v4.0'
   Application Pool that comes out of the box with IIS and I ensured that it was the
   only application running in that pool.
2. Under the 'Advanced Settings...' option for that Application Pool I changed the
   following two settings from their default values, so as to ensure that the process
   would NOT get recycled
   'Idle Time-out (minutes)' = 0
   'Regular Time Interval (minutes)' = 0
3. And then I let the application run for several days and the Memory usage just
   kept on growing.
   Let me know if I can be of any assistance in testing any potential solutions that
   may come out of this bug fix.
   Thanks again. Regards - Michael

[mosullivan3]

Hello, is there some way of finding out how far down in the list this bug item is ? Unfortunately I'm running out of time and options and I may have to abandon using SignalR as part of my solution, if
there hasn't been any sign of progress on this by the end of the month.

[mosullivan3]

Xiaohongt a question for you if I may
Have you tried the same test that you did initially with Chrome using longPolling on IE10 with longPolling ? if so what was the outcome ?

[Xiaohongt]

@mosullivan3 , yes I did run the same tests for long polling on IE, Chrome and firefox , ( I covered IE11, don't remember clear if covered IE10 or not, I will try it on IE10), my results show that long polling in Chrome leaks memory

[mosullivan3]

Hi again Xiaohongt,
your comment 'please double check the application javascript code',
has me somewhat concerned, it sounds like we have a disconnect, I wasn't testing any
code that I wrote, I was testing the Microsoft.AspNet.SignalR.Sample Demo code found at this url
http://www.asp.net/signalr/overview/signalr-20/getting-started-with-signalr-20/tutorial-server-broadcast-with-signalr-20

here are the steps that I took to discover the memory leak with the Sample Demo

1. I compiled the sample in Visual Studio 2013, the only change I made was to upgrade the
   version of SignalR used in the project from v2.0.0 to the latest version i.e. v2.0.2
2. I then deployed the SignalR.StockTicker web application to one of the default
   Application Pools that comes out of the box with IIS7.5 i.e. 'ASP.NET v4.0', ensuring
   that this SignalR.StockTicker application was the only application running in this
   particular Application Pool.
   Note: I specifically deployed this application to a 'Windows 7 SP1' OS when I did this
   test (Windows 8 is NOT an option, therefore I cannot use WebSockets as a transport).
3. I launched IE10 and browsed to this URL
   http://localhost/SignalR.StockTickter/StockTicker.html
4. then over the course of several days I monitored the Windows 'Resource Monitor'
   Memory usage for both the 'iexplore.exe' process and its associated 'w3wp.exe'
   process and I observed that both processes memory usage grew and grew
   Left to run for long enough it will eventually exhaust the amount of Free
   memory available to the system.

So the question that I have for you is, did you conduct a similar test to this or some other
test ?

[Xiaohongt]

@mosullivan3 , I run the Sample Demo code before and also other tests, I can check again on the Sample Demo code. BTW, you didn't mentioned in this issue before that you were just testing the Microsoft.AspNet.SignalR.Sample Demo code, so I didn't know, however my comment is just for generically.

[Xiaohongt]

Verified that with the workaround SignalR longPolling doesn't have memory leak on IE11 /IE10/IE9 and Chrome 34.

[mosullivan3]

Hello, just wondering when this fix is expected to be released ? The v2.2.0 milestone looks to be Past due by 4 months already. Thanks for fixing.
regards - Michael

[halter73]

2.2.0 should be released next week.