AC MX5Cup @ ROAD ATLANTA, Wednesday 17th March 2021

Assetto Corsa Racing Club event
Thanks all for joining tonight. I hope you had fun.
Shame of the server loss. I already reported it so let's hope they find the cause and fix it.
 
Thanks for the race - I enjoyed it despite finishing last. I had some good battles along the way but made too many unforced errors. I also learned I was lifting off far too early for the cars lapping me. At one point I lifted for the whole of the long straight!

On the race length, I thought 40mins was fine. I wonder if on a shorter track with more lapping it might get a bit frustrating for the fast guys constantly having to work there way past us back markers though?
 
I think I had quite a high ping. Other cars were jumping for me to.

Nice racing until I binned it :(
It also might be a physics/main_t issue.
Please run a quick race with the same amount of cars (ai) on the same track. (and select to start last).
Open the "render stats" app and take a Screenshot or tell us your fps, main_t, phy and physlate values when the lights go out.

This should simulate the worst case.
 
Thanks for the race - I enjoyed it despite finishing last. I had some good battles along the way but made too many unforced errors. I also learned I was lifting off far too early for the cars lapping me. At one point I lifted for the whole of the long straight!

On the race length, I thought 40mins was fine. I wonder if on a shorter track with more lapping it might get a bit frustrating for the fast guys constantly having to work there way past us back markers though?
Hi David. Glad you enjoyed it. Hope you stay with us. You did fine. And backmarkers are part of the game. So don't worry about that.
 
Yes, I'm using, if I can find them, the real temperatures in July with clear weather at 12.00. For the track temperature you must add both values so track temperature tonight was 45 degrees celsius.
No 15 was right. You have to add these values to get the track temperature. Confusing, I know.


Brands hatch had air temp of 20 and base road of 15. It also had an ambient variation of 5C. So for the final track temp do you take away 5C i.e. 20+15-5=30 ?
 
Thanks @HF2000 for organising. After Q I was ready for some nice battles with Han and Dennis but with my VR on I did not see that my gear lever was in 2nd and when the red lights came up I floored my gas pedal and found myself in the pits :/ Started from there and had a lot of overtaking action. At some place I found myself in the top 10 but another mistake made me loose a place to @Kek700 . That was the beginning of an epic race to catch up. Finally, in the last lap I got a better exit going onto the long straight and was reeling in on him (in super slow motion). I wanted the inside line by all means and he defended it for his life :D When I touched the grass I lost control and hit him made us both crash just before the server went out. Sorry for that Ernie but it was so much fun to try it at least :) (Real life footage of what happened ;) Ernie vs Andreas )
 
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It also might be a physics/main_t issue.
Please run a quick race with the same amount of cars (ai) on the same track. (and select to start last).
Open the "render stats" app and take a Screenshot or tell us your fps, main_t, phy and physlate values when the lights go out.

This should simulate the worst case.
These are the numbers as the lights go out at the start of the race on my three monitor set up

Screenshot 2021-03-18 092338.png


These are figures if I just use a single monitor and leave all the graphics settings the same...

Screenshot 2021-03-18 093146.png


Another start with a single monitor gives a higher PHY-LATE...

Screenshot 2021-03-18 093901.png


I've also run the three monitor setup again and get PHY_LAT of 900. Confusing.
 
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These are the numbers as the lights go out at the start of the race

View attachment 455861
Thanks for coming back with this so quickly :)
FPS: great, 94 fps is really good. What CPU do you have?

Main_T: 93.6% is a bit high for my liking but shouldn't cause big troubles

PHY_LATE 6007 is really really bad and critical though! My PHY_LATE value is mostly around 0-20 and only slowly getting up with some fps spikes here and there, counting 1 at a time.
You have 6007 when the lights go out?

Can you check if it's going up and up when you start to drive?

In Assetto Corsa, the physics always runs at 3ms ticks. If your PC took longer than 3ms to complete the physics calculation, PHY_LATE goes one number up.

6007 means that your physics calculation was not working correctly for 6007 physic ticks.

It might also have something to do with your ping, but these 6007 might also explain why you're jumping around.

A solution to get the PHY_LATE down would be to limit the fps at a lower value like 85 fps. This should take some load off from the CPU and allow the physics ticks to complete within the 3ms.

I'm don't really know why you can have so many fps but also the phy_late issue. Normally physics should have priority.

Here are two Screenshots without CSP CPU optimizations, 49 AI cars at Road Atlanta, quick race.
Normally my FPS limit is 90 fps and I keep them stable, but this shows clearly that my CPU is struggling.

AC_CPU_Limit_Start.JPG


Frametime 16.3ms, CPU frame time 15.663ms, DIFF 0.633 (GPU frame time).
Main_T at 94,7%, which is the maximum I have seen yet.

But somehow PHY_LATE is only at 28.

(I don't know why PHYS on the left is showing 0.000. Maybe it's an old value.. I was driving, no replay).

Here's the same quickrace after 1 lap:
AC_CPU_Limit_1Lap.JPG


You can see that my PHY_LATE ticked up a few times when my CPU had some spikes and couldn't keep up.


Conclusion:
We have to look into "how to fix PHY_LATE".
My CPU has 6 cores and 12 threads so although I'm in the Single Thread Performance Limit and the fps go down, my CPU has a lot of headroom. Overall load was only at 35%.
If you have fewer cores than me, it might be that your overall CPU load is close to 90-100%?

Can you do the same test again but do a full lap and then take the same screenshot?
And can you also activate the "Graphics Stats" app? It's a bar graph icon for me.
 
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Well that sucked. I was racing ok - could have been better. D/C'd from connection issue starting the last sector of the last lap.. what luck! I would have finished if I didn't have to stop for fuel because of putting 30m of fuel in! :thumbsdown:

Sorry for the bump a few laps in Omar. I hope it didn't ruin your race!

I still have to have a look at the reply, I was bumped from behind on the uphill chicane at half race but I don't think it was you, I spun and lost lots of time. Will try to clarify with the counterpart once I see who he was.
I believe that you bumped me on the last chicane? Had you the same yellow car as I had? If so, that didn't harm me too much (except for my self esteem, that is)
 
Thanks for coming back with this so quickly :)
FPS: great, 94 fps is really good. What CPU do you have?

Main_T: 93.6% is a bit high for my liking but shouldn't cause big troubles

PHY_LATE 6007 is really really bad and critical though! My PHY_LATE value is mostly around 0-20 and only slowly getting up with some fps spikes here and there, counting 1 at a time.
You have 6007 when the lights go out?

Can you check if it's going up and up when you start to drive?

In Assetto Corsa, the physics always runs at 3ms ticks. If your PC took longer than 3ms to complete the physics calculation, PHY_LATE goes one number up.

6007 means that your physics calculation was not working correctly for 6007 physic ticks.

It might also have something to do with your ping, but these 6007 might also explain why you're jumping around.

A solution to get the PHY_LATE down would be to limit the fps at a lower value like 85 fps. This should take some load off from the CPU and allow the physics ticks to complete within the 3ms.

I'm don't really know why you can have so many fps but also the phy_late issue. Normally physics should have priority.

Here are two Screenshots without CSP CPU optimizations, 49 AI cars at Road Atlanta, quick race.
Normally my FPS limit is 90 fps and I keep them stable, but this shows clearly that my CPU is struggling.

View attachment 455879

Frametime 16.3ms, CPU frame time 15.663ms, DIFF 0.633 (GPU frame time).
Main_T at 94,7%, which is the maximum I have seen yet.

But somehow PHY_LATE is only at 28.

(I don't know why PHYS on the left is showing 0.000. Maybe it's an old value.. I was driving, no replay).

Here's the same quickrace after 1 lap:
View attachment 455878

You can see that my PHY_LATE ticked up a few times when my CPU had some spikes and couldn't keep up.


Conclusion:
We have to look into "how to fix PHY_LATE".
My CPU has 6 cores and 12 threads so although I'm in the Single Thread Performance Limit and the fps go down, my CPU has a lot of headroom. Overall load was only at 35%.
If you have fewer cores than me, it might be that your overall CPU load is close to 90-100%?

Can you do the same test again but do a full lap and then take the same screenshot?
And can you also activate the "Graphics Stats" app? It's a bar graph icon for me.

Here is the start again

start.png


PHY_LATE seems to have calmed down

This is after lap one

onelap.png


The PC spec is not super powerful but it runs fairly smooth if I play with the graphics settings...

Intel i5-6400 2.70GHz
16GB Memory
Nvidia GeForce GTX 1050 Ti
1TB SSD

ping usually around 30 but not sure what is was yesterday.

What is the "Graphics Stats" app? Where can I get it?

Thanks for your help
 
I still have to have a look at the reply, I was bumped from behind on the uphill chicane at half race but I don't think it was you, I spun and lost lots of time. Will try to clarify with the counterpart once I see who he was.
I believe that you bumped me on the last chicane? Had you the same yellow car as I had? If so, that didn't harm me too much (except for my self esteem, that is)
I don't have a replay file. I'm assuming it's because of the server crashed. Does anyone else have one?
 
Excellent race after a two-week break! Ended up P10 with a new PB so that puts a smile on my face. :D

Sorry for the horrible timing @pattikins :redface: .... should have kept my line and I probably would have done less damage. Glad you ended up P1 but I took you out of a proper battle.

Thanks for the close racing @JamKart22 and @Giovanni Chiarotto it was quite enjoyable :). Jam, I not sure you are aware but you are jumping all over the track (connection reliability?) and it's quite tough to gauge overtakes, so, apologies if I messed you up at all.

Enjoy the rest of your week, everyone. Thanks for a great race and I'll hopefully see you all on Sunday!

Yes, it was a nightmare being behind @JamKart22 and I was always scared of possibly interfering / harming him without wanting. I assume it was the same you saw of me when I had a worse connection, now I understand how important the ping value is :(
 
Here is the start again

View attachment 455881

PHY_LATE seems to have calmed down

This is after lap one

View attachment 455882

The PC spec is not super powerful but it runs fairly smooth if I play with the graphics settings...

Intel i5-6400 2.70GHz
16GB Memory
Nvidia GeForce GTX 1050 Ti
1TB SSD

ping usually around 30 but not sure what is was yesterday.

What is the "Graphics Stats" app? Where can I get it?

Thanks for your help
GraphicsStatsApp.JPG


It's a developer app, oops:
1616063738484.png


I think the issue is that your i5-6400 is powerful enough to get pretty high fps but doesn't "spare cores" so your overall CPU load gets pretty high.

Ping = 30 should be absolutely perfect and not causing issues!
Is that your ping in AC on the RD servers?

Then you either have massive "package loss" (I don't know how to see this in AC though...) or it's indeed the phys_late issue.

I fear the only solution would be to limit your fps at a lower value so your CPU has enough headroom.
If you get the graphics stats app running, we can spot what's tanking the CPU the most!

Do you have any programs running in the background? Chrome, anti-virus, streaming, anything that pops into your mind? (Apart from Discord ofc)


About your triple screen screenshot with the 6007 phy_late:
Your fps are over 90 in that screenshot while all the others are in the 70's.

That's the only real difference I can spot there.

Phy_Late close to 1000 isn't great though.. Not super bad, but it really should stay below 100 for an hour long race :(
 
Yes, it was a nightmare being behind @JamKart22 and I was always scared of possibly interfering / harming him without wanting. I assume it was the same you saw of me when I had a worse connection, now I understand how important the ping value is :(
Ping causes bigger jumps. Like the car in front of you is driving 20m and then teleports to somewhere else.
I've watched the Okayama GT3 replay and it's not like Colin is teleporting around, he's rather hopping a little bit all the time, like his car would be a nervous bunny :roflmao:
 
View attachment 455884

It's a developer app, oops:
View attachment 455885

I think the issue is that your i5-6400 is powerful enough to get pretty high fps but doesn't "spare cores" so your overall CPU load gets pretty high.

Ping = 30 should be absolutely perfect and not causing issues!
Is that your ping in AC on the RD servers?

Then you either have massive "package loss" (I don't know how to see this in AC though...) or it's indeed the phys_late issue.

I fear the only solution would be to limit your fps at a lower value so your CPU has enough headroom.
If you get the graphics stats app running, we can spot what's tanking the CPU the most!

Do you have any programs running in the background? Chrome, anti-virus, streaming, anything that pops into your mind? (Apart from Discord ofc)


About your triple screen screenshot with the 6007 phy_late:
Your fps are over 90 in that screenshot while all the others are in the 70's.

That's the only real difference I can spot there.

Phy_Late close to 1000 isn't great though.. Not super bad, but it really should stay below 100 for an hour long race :(

Where do I get the graphics stat app?

Would limiting it to 60fps make it look poor or is that still acceptable?

I just hopped on the RD server and measured a ping of 30
 
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Where do I get the graphics stat app?
You need to enable developer apps, like shown in the screenshot.
Are you using content manager?
Would limiting it to 60fps make it look poor or is that still acceptable?
I used 60 fps on my 60 hz monitor for years. Absolutely fine!
You get more "updates" for things like braking points at 250 kph with higher fps but 60 fps is definitely fine!!

The question is linked to:
Are you using vsync,gsync,freesync,etc and what's the refresh rate (hz) of your monitors?

If you're currently syncing them at 72 fps/hz, limiting to 60 fps will probably stutter.
If you adjust all the sync options to 60 fps/hz, you probably won't be able to tell any difference!
I just hopped on the RD server and measured a ping of 30
Alright, so it's 99% surely the phys_late which is causing the bunny hopping we see from your car.

What you could try is to set "Skip FFB Steps" to 1. This means that your FFB update rate is a bit lower. Still good enough for everyone, I didn't feel a difference when trying.
But apparently it can give the CPU some headroom, when close to the limit.

Again, are you using content manager? Then here's that setting (currently at 0 for me).
If you're not using content manager (you should hehe),
then I can get you the line in the ini files.

AC_FFBSkipSteps.JPG
 

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