Extremely Elusive Stutter Issue

[pdmarsh]

For over a year I have been living with, and trying to isolate, an in-game stutter issue that I experience when flying DCS. Thinking it was related to external hardware, I completely isolated all external inputs going into my PC, including Ethernet and speaker connections, and still experienced the problem. Since none of the folks I fly with seem to have this exact problem, I assumed it was not related to DCS directly. However, I do not see the same issue when I fly X-Plane, although I do get an occasional stutter there. I also thought it might be the PC itself, but I recently built a new one and have the same issue. Finally, I thought it could be our home electricity. I ran DCS on my laptop on battery power and still saw the spikes I will mention below. A test device showed no problems with our electricity. I also made sure no scripts were running and still saw the issue. One final oddity about this is that when the stutters occur, DCS apparently rescans my input devices and resets anything not currently in sync with the sim. I see this mainly with zoom when my zoom lever is not synced with the default view. If I am in default zoom in-game and one of these stutters occur, my screen view will jump to whatever the input device zoom lever is set to. In fact, I originally thought I had a bad controller way back when this issue first appeared. This rescan of input devices has occurred on two PCs that show the stutters and with different controllers.

 

Each of the spikes seen in the attached MSI Afterburner chart (“GPU usage” mainly, but also in “FB usage”) coincide with significant on-screen stutter. In this case they were coming at the rate of every 20 seconds or so. When I have this issue, it isn’t always as regular, but usually it is fairly regular. However, there can be sessions when I have no MSI spikes or on-screen stutter at all. It can happen in single or multi-player mode. It happens with different modules. The stutters themselves can vary in intensity and sometimes I’ll see the MSI Afterburner spikes but not have on-screen stutter at all, but this is somewhat rare. I even thought that MSI Afterburner itself might be a problem, so I ran DCS with it completely closed, i.e. not running in the background, and still had on-screen stutter.

 

If anyone has any idea at all as to what the root cause of these stutters might be, that input will be greatly appreciated.

 

The following systems specs relate to the PC that produced the attached MSI charts.

 

DCS Version: Currently running 2.5 Open Beta but have had the issue in 1.5 versions as well.

Windows 10 - 64-bit

GIGABYTE GeForce GTX 1080 Ti 11GB 352-Bit GDDR5X PCI Express 3.0 x16 ATX Video Card

Intel Core i7-7700K Kaby Lake Quad-Core 4.2 GHz

ASRock Z270 Extreme 4 LGA 1151 Intel Z270 HDMI SATA 6Gb/s USB 3.1 ATX Motherboard

SAMSUNG 960 EVO M.2 500GB NVMe PCI-Express 3.0 x4 Internal Solid State Drive

G.SKILL TridentZ Series 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 3200

 

DCS log file attached.

 

Thanks,

Paul

dcs.zip

[Nealius]

Have you noticed any "triggers" with your stuttering? I frequently find that if I'm flying straight and level for a period of time, then initiate some kind of maneuver--turn, climb, roll, whatever--I will get a stutter. I also get stutter whenever I release weapons.

[Floyd]

Maybe the power limit is too high or the fan limit too low?

[pdmarsh]

Have you noticed any "triggers" with your stuttering? I frequently find that if I'm flying straight and level for a period of time, then initiate some kind of maneuver--turn, climb, roll, whatever--I will get a stutter. I also get stutter whenever I release weapons.

 

@Nealius -- Thanks for responding. So far I have not seen any trigger or any pattern at all related to this, but I will continue to look for some common thread.

 

Paul

[pdmarsh]

Maybe the power limit is too high or the fan limit too low?

 

@Floyd -- Thank you for responding. I tested this with MSI Afterburner disabled, so that particular profile would not have been running. Also, I have this issue on three separate PCs, all running with and without Afterburner. There has to be a reason for this, but I am running out of things to check. During the session associated with the graphic I posted, DCS was all but unplayable. I can usually live with it, but that one was pretty bad.

 

Thanks again,

Paul

[sslechta]

When I had stuttering on my GTX970, I resolved it in the NVIDIA Control Panel from tips here on the forums. I haven't tested to find the exact setting that fixed it but in Control Panel:

 

- Turn on Antialiasing - FXAA

- Vertical Sync - ON

 

Then in the DCS settings I turned off MSAA and the Vsync checkbox.

 

BOOM! Stuttering stopped immediately. Let us know if this helps.

[pdmarsh]

When I had stuttering on my GTX970, I resolved it in the NVIDIA Control Panel from tips here on the forums. I haven't tested to find the exact setting that fixed it but in Control Panel:

 

- Turn on Antialiasing - FXAA

- Vertical Sync - ON

 

Then in the DCS settings I turned off MSAA and the Vsync checkbox.

 

BOOM! Stuttering stopped immediately. Let us know if this helps.

 

Thank you, Steve. I came across those or similar posts as well and I'm fairly certain I'm using those settings, but I will check to be sure this evening. Even if things appear to get better, only time will tell if it's gone for good. Each time I think I have found the source, I have been proven wrong. As I mentioned, this one has been elusive.

 

In any case, I appreciate the input.

 

Paul

[Chic]

Can you run DCS in "Safe Mode"?

[BitMaster]

My assumption is a USB problem, some firmware seems to reinitialize and throw it all over, again and again and again, endless.

 

If you have a PS Keyboard, deattach ALL of your USB but the mouse if need to be, then fly a testflight with keyboard only. If nothing interferes then you may add one after the other.

 

It may not be the device itself but the Port aka Chipset/Firmware/driver you connect it to.

It may well be that a variety of devices will trigger this on certain chipsets. TiR could be one of them as stutter seems to be more apparent these days.

 

I think it is triggered by the way DCS usues the system but not a DCS fault. Other games and flightsims my solve their tasks differently and by coincidence don't trigger the effect. That is my guess.

 

You can also deactivate some of your USB ports or all in Bios. See if that shows some change.

 

If, in any case, a certain USB port(s) turns out to be probelamtic, verify it's driver and details and counter-check with your motherboard supplier or USB chip vendor if they offer a newer driver. if they dont, this site for sure has them: win-raid.com in the forum section you will find

the info and downloads for newest USB chipsets drivers. RTFM ! you most likely will need to import certs too if you want those drivers.

 

 

If you hear the USB ding-domng sound a lot while not connecting or disconnecting any USB, that is a clear sign of a USB problem, either driver, device or Voltage ( VCC-IO & VCC-SA ) if you run an overclock or have an unlucky Bios with bad settings.

 

Usually those Volts are 0.95 and 1.05 for Io & SA. Most boards by default run them at 1.3 and beyond, this can easily cause USB errors and BSOD's. I learned a lot fighting those two settings since Z170 chipset. If you dont overclock, I recommend to manully dial in the correct Volts and not Auto setting. You can check where those Volts are and then decide.

 

As a rule of thumb, those 2 values are very critical when OVERDONE ! You may run your CPU and GPU and RAM with more Volts then needed if you can cool them but that will not work with those two. The need to be more or less pretty precisely set. Good overclocker guides cover this part in detail and mention the USB and DDR sideeffects of said values.

[pdmarsh]

Can you run DCS in "Safe Mode"?

 

Thank you, Chic. It's a good test--I'll give it a try.

 

Paul

[pdmarsh]

My assumption is a USB problem, some firmware seems to reinitialize and throw it all over, again and again and again, endless...

 

@BitMaster--I felt from the start it was related to USB, but after disconnecting every single USB device, including the dongle for the mouse and keyboard, and still seeing stutters, I realized the devices themselves were not the issue. I didn't think about the drivers. I'll make sure they are updated. Thanks for all of the other input as well.

 

Paul

[BitMaster]

If you still "feel" that it is a USB thing, then dig deeper !

 

Your Case's Frontpanel usually acts as a Hub, disconnect it on the mobo.

Same with all other internal USB connectors, take them out and check.

 

I wonder what one could do, if it turns out to be a bad ASmedia,Ti or NEC USB-Add-on implementation. Deactivate it and buy a card instead ?

 

What makes me think in an even other direction is that you can reproduce it on 3 PC's as you say. 3x bad luck is not the norm, you know what i mean. What is the common part of those 3 ?

Do they share any software or specialties ?

 

I had a bunch of installs since 2012 and luckily, all but 1 went smooth ever since. The usual errors and pains but no stutter that gsync couldnt fix and no crashes other didnt have too.

DCS usually runs ok is what I can say looking at my own records. It's not that it by definition

needs special skills or hardware or such. Install, launch 'n' fly does work. That's what puzzles me many times, how installs can go south by little differencies, unnoticed by anyone.

 

Have you done a latency check ? Check your latency with latencymon, run it while you fly.

Not too long ago, mabye 1-2 weeks, LM didnt solve the problem, but it found the cause.

 

Again, if LM says your latency sucks, what can one do to fix it ? Nothing, you have a bad motherboard, i mean badly designed. maybe a new Bios helps, maybe not. Latency is crucial

and nothing but a gamble. it either slips and slides like greased or it stutters every now and then.

 

Anyway, curious to hear what you find out

[pdmarsh]

@BitMaster -- Thank you for the additional input. I'll run some tests with LatencyMon and WhySoSlow to see what they might find. I'll also keep looking for commonality between the three PCs where I see the effect. To clarify that I bit, my first sim PC and the new one, now running in different locations with different input devices, both show the exact issue of on-screen stutter associated with the spikes seen in the MSI charts. My third PC is a laptop which shows the MSI spikes, but I'll need to test again to look for on-screen stutter.

 

Thanks.

[BitMaster]

In another thread a guy fixed it by RESETTING his Nvidia-Cpanel.

 

Try it, takes 15 secs ! Would be cheap and a big:doh:

[Flappie]

Hi Paul, I know this seems non-related, but would you mind checking that your 1080Ti is plugged into the top PCIEe slot of your motherboard? It's the one named PCIE2.

 

I see in the manual of your motherboard, page 19, that only the top slot (named "PCIE 2") allows x16 speed. My idea is that, as you use an NVMe SSD drive, a PCIE bottleneck could screw with your SSD and cause those weird issues on top of the game stutters. Anyway, this will only take 5 minutes to check.

[pdmarsh]

In another thread a guy fixed it by RESETTING his Nvidia-Cpanel.

 

Try it, takes 15 secs ! Would be cheap and a big:doh:

 

Sadly, no joy. But thanks for the suggestion.

 

Paul

[pdmarsh]

Hi Paul, I know this seems non-related, but would you mind checking that your 1080Ti is plugged into the top PCIEe slot of your motherboard? It's the one named PCIE2.

 

Thanks Flappie--Good thought, but all is OK in that regard.

[pdmarsh]

OK, here are some updates and comments on my issue. First, it is not resolved. I have tried all of the suggestions made here or that I have found on the internet for others with this issue and none have worked. Regarding others, if you do a search on what causes repeating spikes in the MSI Afterburner GPU Usage chart, you will find a number of posts with people who have either the exact issue I have, or something quite similar. One very interesting post (HERE) claims that sometime over the last year Nvidia has acknowledged a stutter issue and is working on a fix. My problems started about a year or so ago. Also, these posts seem to all relate to Nvidia cards. Hmm. I just got off chat with Nvidia and the tech claims to not be aware of this and will not comment on 3rd party posts. I get it. He was very willing to dig, but I could not stay on any longer. Plus, I really just wanted confirmation of the acknowledgement, which I did not get.

 

The primary commonalities between the two PCs that clearly have the exact same issue, and my laptop which shows the MSI spikes, are Nvidia graphics cards and DCS World. I re-ran X-Plane and took a much closer look at the MSI charts. If I strain my eyes, I might see hints of similar spikes. However, I never experience the repeating on-screen stutter in X-Plane. However, I sometimes get a single episode of stutter during a long flight, but it clears and does not repeat. Also, and sorry to repeat myself, but I have completely closed MSI as a potential source itself and I still get stutter in DCS World. Anyway, I assume that DCS and X-Plane utilize PC resources differently. One might expose an issue while the other does not. I do not believe mine is a DCS issue per se.

 

I appreciate the time and input from all--thanks. There has to be an answer and I'll post any updates.

 

Paul

Edited April 6, 2018 by pdmarsh

[BitMaster]

That would indeed be a bad situation if Nvidia themselves screwed it up.

 

It seems to be not with every Geforce card, as some have it ( I dare to say the minority ) but most luckily do not experience that stutter.

 

What a misery, one spends that much money on a rig and is doomed before putting it together.

 

That idea makes me sick, a sit leaves no choices but change HW until it works, not really practicable.

[Nealius]

Are these spikes an increase in GPU usage? I just ran a test flight and noticed that every time I experience stuttering, my GPU usage dips. Here's a screenshot of what I noticed with my stuttering.

 

Edited April 7, 2018 by Nealius

[pdmarsh]

Are these spikes and increase in GPU usage? I just ran a test flight and noticed that every time I experience stuttering, my GPU usage dips. Here's a screenshot of what I noticed with my stuttering.

 

My situation is the same--when the stutter occurs, GPU Usage drops to near zero and almost immediately back up to the normal area. Sometimes the stutter lasts a few seconds, other times it's a blip. Very interesting that you see this as well. The severity of the issue varies. Some nights I get no spikes or stutter at all. Most times I get some. Other times, DCS is almost unflyable.

 

Thanks,

Paul

[Nealius]

This flight tonight with that screenshot was one of my better days. Last night I had horrible stutters. Before both flights I deleted the fxo and metashaders folders. There doesn't seem to be any consistency on bad days vs. good days. I also can't figure out if my CPU dips, disk usage spikes, or ethernet spikes are connected. Sometimes they appear to occur at the same time as the GPU dips/stutters, other times it's only the GPU dips that occur during the stutter.

 

I should note, Disk 0 is an HDD with my OS, and Disk 1 is an SSD with DCS.

[toutenglisse]

Just a though.

Stutters are most times due to stuff loading for a reason. (anti-virus scan, radius loading,...)

Nealius on your screenshot stutters occure with Gpu usage dipping and Disk access spiking.

Gpu usage dipps because stuff loading so nothing to work on till loading is finished.

 

Trial balloon : declare your DCS install folder (or even just BIN folder) in your anti-virus exceptions (so no risk of intempestive scan during fly), and be sure to use the max preload radius in DCS settings. (probably with min preload radius DCS would load stuff often, inducing stutter)

[Nealius]

I have no anti-virus software, other than the default Windows Defender. I turned scans off.

 

The disk usage was from my OS drive, which I find odd. No anti-virus to do a scan, and with DCS on the HDD it shouldn't be loading anything. Maybe writing the metashaders/fxo folder or something in the Saved Games folder?

[toutenglisse]

Nealius - yes possible. Loading/writing stuff to these folders in savegame.

 

Or maybe it's an external process ?

 

I don't see other thing than setting preload radius to max (I read it's a prerequisite for accessing some MP severs, surely because it has something to do with stutters due to loading stuff if setting is not max)