Network latency issue 1.0.14

[Jess-b]

Hi Peter,

I'm having an odd issue with joinFS 1.0.14. I flew with friends this morning and for the first part of the flight, all was well. After a stop at one airport, one member of our group changed their aircraft from a real air Duke to a carenado P46. At that point I started experiencing issues with the other guys aircraft. Their aircraft began throwing themselves around like mad. Leaving the session and rejoining calmed things down for a few moments, but the problem returned. Changing back to the original duke did nothing.

Checking the network I discovered my network latency pings were stretching to well over 1 second to 3 seconds and back to normal. Only I out of five pilots was suffering this issue. I checked my network connection, but with a 1000mb Ethernet connection and a 125Mbit download speed, it wasn't causing an issue. Windows reported next to no load on my connection as I'd expect with joinFS using so little bandwidth.

Where things get weird is when I switched focus from P3D v3.4 to Activesky 16. With the focus on that window and not the sim, the latency returned to normal and all aircraft behaved as normal. Switching back to the sim and all hell broke loose again. I'm at a loss to explain why this is. Others in the Same session were also using active sky 16 with no ill effects. Any ideas what the issue is?

Best wishes,
Jess B

[ATC Roo]

Just curious but...

Was ATC mode ticked in settings?

[Peter]

Hi Jess,

this is quite interesting, I was flying with a group this evening because there were a couple of issues, and one of them sounds very similar to your scenario. Everything was pretty fine between six players, but a seventh player was seeing aircraft fly about, but only when approaching close to the other aircraft. Another odd effect that may be related was that their callsign was empty, which it shouldn't have been.

Hopefully I'll be able to piece these things together and find the cause of it.

Thanks for posting about it.

Peter

[Peter]

Hi Jess,

can I just check, which version did you use prior to 1.0.14, and did you see any problems with that one?

Thanks,
Peter

[Jess-b]

Hi Peter,

I actually used 1.0.15 test prior to that and saw similar results. It's all very odd.

[Peter]

I guess you have your frame rate limited to 35, but just checking anyway?

There is a chance that there was a mismatch between versions. Could some people have connected with 1.0.16. This would definitely cause problems, but won't be a problem after 1.0.17 because I've added a check for the network data version which will mean you can only connect to people with completely compatible versions. I was trying to make them backward compatible, but it was very difficult to do so and not really necessary.

It's strange that when you task switched it became stable. Does this happen every time you task switch?

When it happens do you see anything bad in the View|Monitor window? If so could you PM me with log.txt from <user>\AppData\Local\JoinFS\

Thanks,
Peter

[Jess-b]

Yup I was locked at 35 and we were all using 10.0.14. I'll grab the log file and pm it to you today Peter.

[Jess-b]

Hi Peter,

Sorry for not getting back to you sooner. I'm currently flying using 1.0.21 no the issue has returned. Again switching focus from P3D to Activesky 16. Checking the monitor I'm seeing an error marked 'simconnect exception 3'. Does this help in any way?

Jess B

[Peter]

Hi Jess,

this is an unusual one. I also have AS 16 and haven't seen this problem, I doubt it is directly caused by it per se, and I know one or two others who use P3D without this issue. Would you be able to try it next time without AS running, just to see what happens? Perhaps there is an issue with SimConnect.

Do you notice the problem when switching between other applications and P3D?

That exception error does occasionally happen, I think I fixed a lot of those in the latest version but it wouldn't surprise me if it still occurs. I will keep a look out for that.

Does the latency issue happen all the time or does it start happening suddenly during a flight?

In P3D, I assume that you have it configured to not pause on task switch?

Sorry for all the questions, it would be nice to find the cause

Peter

[Jess-b]

Hi Peter,

I'm not sure it's directly related to AS16. I can switch to other programs like plan G and p3d settles fine. Weirdly, the problem sorted itself out during the flight. My one thought on this could be due to cloud cover. At the start, the weather was incredibly poor. My frame rates were ok, sitting at 35 or there abouts. As the flight progressed and the cloud coverage cleared, the network issue disappeared. It's really quite baffling.

Jess B

[Jess-b]

Hi Peter. Sorry to dig up an old thread, but I'm still suffering the same latency issue with the current joinFS version. The solution still seems to be to switch focus onto AS16, which seems to keep everything under control. Once I focus back in the sim, the latency stretches out and everyone spins, loops and generally goes nuts. I've been monitoring the latency and have seen figures as high as 3000ms and more. It's all very odd. Checking today's flight the log lists the following issues.

SimConnect 3.4.0.0
Lockheed Martin P3D v3 3.4.22.19868

And a few simconnect exception 3 errors.

I'm really at a lose here.

Jess B

[Peter]

Hi, Jess.

thanks for the update on this issue. I was rather hoping that a little change I made in 1.1.6, I think it was that version, was going to sort the problem out. Can I just check, are you still seeing this with the latest test version 1.1.7, or are you still using the stable version 1.1.4?

The strange thing is I've not seen any similar reports of this, and there's quite a number of JoinFS users now. So, a request to anyone else reading this post/thread, and is experiencing the same thing, please let us know what simulator/hardware you're using and perhaps we can find the cause of it.

If you only see a few "exception 3" errors, it's unlikely to be that. I'll try to get those cleared up soon anyway.

So, when you go from P3D to AS16, do the latency values change significantly? 3000ms is definitely too high, and is likely to be related to the problem. Usual and acceptable values are between 100 and 500, for smooth updates.

Peter

[Jess-b]

Hi Peter.

I'm currently using 1.1.4 stable as my current client. I'm really puzzled by this. I'll download 1.1.6 and see if there's any change. But since this is entirely localised to me alone, I'm beginning to suspect it's my ISP. It's a cable connection with a 125mbit down and 12.5mb up connection. It uses IPv6 only though. Anyway, will check and report back.

Jess

[Peter]

Your ISP speed sounds great, however IPv6-only may be a problem? JoinFS only uses IPv4 and doesn't support IPv6. However, I'm surprised that it would work at all if your network connection was purely IPv6. I assume that it is also able to provide IPv4 as well, but perhaps those connections are limited in some way?

I'll do a bit of research on it.

Peter

[Jess-b]

Hi Peter.

Yes my isp only provides me access to an IPv6 address, though it does provide a spoof IPv4 as well. I can't use that ipv4 to host Though.

[Jess-b]

Ok, I've had a sort of breakthrough.

Here's what's interesting. I'm using 1.1.16. So flying today as normal I'm not seeing any issues. That is until I open a secondary joinFS window. Say I open aircraft window, and leave it open, I get the latency issue. Once I close it. All Is well. Not sure what to make of that. But as long as i only have the main joinFS window open, everything is good. What do you think Peter?

Best wishes,
Jess B

[Peter]

Hi Jess,

thanks for posting about this. Firstly, if it gives you a work around for the problem then that's great. But also, it does suggest that the current underlying way that everything is being processing is called into question. It currently relies on some high level Windows events that I had previously thought would be adequate, but this may well not be the case. It may also explain why on a lot of systems everything looks nice and smooth but some people are seeing the aircraft jump around a bit or have similar synchronization issues.

I definitely think it's worth re-implementing this side of things and it certainly won't do any harm. So thanks for helping to find what could be a significant issue.

Best regards,
Peter

[Deano1973]

Just seen this post and wanted to add that I've noticed lag in other aircraft on occasion and discovered that the pilot had brought up their Teamspeak window to read a message or opened up an Internet screen to Google something. It seems as though performing any other action while inside FSX can cause jitters in JoinFS, not just opening a JoinFS window while in flight.

[Peter]

Well that definitely adds weight to the theory.

The next test version may be a little bit longer.

Peter

[Jess-b]

Well I'm glad we're getting somewhere. it also explains why I've been suffering with latency issues while I'm looking at the nodes window, trying to solve my latency issue. Still don't know why bringing up the active sky window was solving the issue, but if you're right Peter and the issue stems from what joinFS is doing in the background with windows, I guess switching to active sky made windows reprioritise a few things. I'm just sorry it's going to cause you so much grief!

Today's flight finished without any incident at all. So that's something.

Best wishes,
Jess B