My version on how to get smooth and stutter free P3D 3.1

[SteveW 1,792]

Making four LPs by turning off HT is not the way to go about this John. Simply unmasking LPs on any system will cause P3D (and FSX) to utilise the CPU more by creating more jobs, but for no additional gain in performance.

 

CPU utilisation is not a measure of sim performance, many get this wrong. I would like to see five LPs running better than four on my six core, but it gets worse with five, a little more worse when adding a sixth. But more than four doesn't work so well whatever the setup.

 

Increasing the scenery load with hi res ORBX and airports loading up the sim improves the effect of having the jobs optimised since they take *longer*, making it harder to require more than four jobs.

 

Unmask only 4 LPs with HT enabled, ignore the total CPU utilisation in Task manager.

[SteveW 1,792]

Remember I also pointed out the even load across all LP's when selecting the am through process lasso once the sim was running. But Steve advised me against this due to the sim not behaving as it should.

Yes, that's correct.

 

Very basically, start up the sim with no AM on a four core HT enabled, and it will make 8 jobs. Then apply an AM with proc lasso or task manager and those 8 jobs all bunch up onto the remaining unmasked LPs. Change the AM again and they stay bunched up where they continue absorbing throughput from each other.

 

We have to get the foreground task on a core of it's own, and keep addons off it since addons by definition run with the sim. Other tasks cutting in on the main sim job on the same LP or on the HT partner LP will make the main job sawtooth. The jobscheduler is good, and will ignore this core once the sim is up and running, stating other tasks elsewhere.

 

Get the background sim tasks away from the main sim job too, just like addons they too will eat into the performance of the sim. The second sim job does not run with the throughput requirements of jobs 1, 3, and 4.

 

The background sim jobs can take a number of seconds to complete. John says "I am not a frame hunter", that's a good idea. Watching the sim start up and trying to judge fps behaviour won't help, and the different way the concurrent tasks play out during startup can really fool you. The sim needs time to settle-in with a setup and get underway.

 

 

...reminds me of the old BufferPools tweak in FSX.

 

There was the UsePools=0 camp (let's call them the HT Off guys), and there was the Poolsize=549872613 camp (let's call them the No AM guys).

 

But with purpose designed software, specifically to measure the performance of the sim, it became apparent that what was actually needed was just a small bufferpool.

[Guest]

Steve or anyone,

 

I had an odd situation with AM just yesterday with P3D V3.1 ... I had setup AM so Core 0 was not to be used, started P3D and verified it core 0 was not being used by P3D ... but after some flying I ran a quick check and saw that core 0 did have "some" utilization from Prepar3d.exe ... it wasn't a lot, but it was "some" (about 10%).  There was no apparent change in long frame frequency when this happened, but I'm curious as to how/why this happened (HT OFF 8 real cores enabled).

 

This is with Windows 10 box, I wasn't able to replicate it on my Windows 7 box.

 

Just thought I'd share this oddity ... don't know if it's a Win10 issue or an LM issue or add-on triggered (I think Virtuali attempts to do AM management on the fly), or maybe even a hardware issue?

 

Cheers, Rob.

[SteveW 1,792]

Yes this can happen, since the use of Windows resources spawns threads down the line, as many as 50 or more. The jobscheduler can start these outside of the affinity of the app, but software can report it owned by the app. Take ntdll.dll for example, folks swear they don't link to it but it's calls are utilised by pretty much all Windows programs and not called directly by the app.
 

...Rob, since you have HT Off, the spare core was targeted by the jobscheduler as underutilised. If HT was enabled, and you had correctly *masked one LP of the first core that the sim encounters*, the jobscheduler would not use the other "underutilised" LP of that core, since it's actually an LP of a well-utilised core, but would continue to find the next underutilised core.

Take a look at this over simplified lay-mans diagram of HT Enabled vs Disabled:

[klamal 282]

I hope you don't mind me asking as I've only been watching from afar but, the gist of all these related topics for P3D now is to have HT on and then use an affinity mask. Correct? Even for an i5 2500k? Should I enable HT? I am currently overclocked to 4.5 as well. Enabling HT I think means we want to then lower or turn off overclocking then?

 

Thanks so much for any answer/advice and for all the research that has/is being done!!

[vgbaron 3,616]

I have a 3770 clocked to 4.7 - the temp difference between HT on or off is minimal IN MY SYSTEM. Some people generate too much heat with HT on thus need to reduce their clock. Enable HT and take several flights in heavy cloud cover, etc and watch the CPU temps.

 

Vic

[Gemelli 0]

i have an i7 4930k 6 cores, how come when i turn on HT on my sim is more stutter and when it off more smooth? i try it on with AF Mask of 1364 was not bad but with off and AF mask of 62 much smooter

[SteveW 1,792]

 

how come when i turn on HT on my sim is more stutter

Perhaps you didn't run the test enough after rebooting with HT enabled, and should have allowed plenty of time for caching? Otherwise your account does seem not to make much sense, the opposite of my findings.

 

I found HT improves performance. I tested the 6 core very recently with heavy set-up. HT On 1360 beat 1364 in every test I did. I turned off HT, 60 beats 62 in every test, both visibly worse performing than HT On, and the overall zap of the PC was hit too. I would say go back and re-test.

 

If HT enabled cannot improve performance then what is everyone buying into it for?

 

I hope you don't mind me asking as I've only been watching from afar but, the gist of all these related topics for P3D now is to have HT on and then use an affinity mask. Correct? Even for an i5 2500k? Should I enable HT? I am currently overclocked to 4.5 as well. Enabling HT I think means we want to then lower or turn off overclocking then?

 

Thanks so much for any answer/advice and for all the research that has/is being done!!

Most extra heat from HT enabled comes from the sim making threads for double the job count, which doubles the core use and increases heat a great deal. By unmasking only four LPs for the sim to start up with we curb the stacking of jobs onto the cores unnecessarily. The same goes for all kinds of processes running on the CPU, most apps stack up two jobs per core instead of one, since they don't have AMs. So we need to keep an eye on heat, HT On will be hotter, but horror stories of overheating and great VAS consumption is due to No AM.

[Gemelli 0]

SO HT on with AM of 1364 should be the best?

[SteveW 1,792]

HT Enabled yes, but whether you can get more out of 5 LPs 1364=(01,01,01,01,01,00) over 4 LPs 1360=(01,01,01,01,00,00) is doubtful and uses more VAS. On top of that 1364 (5 LPs) also gives less room for the other stuff running, only one spare core, but 1360 has two spare cores.

 

For the 6 core HT enabled, I would try 1360=(01,01,01,01,00,00) with the cfg, and put exe addons on 2698=(10,10,10,00,11,10)=A8A or 4046=(11,11,11,00,11,10)=FCE with a .bat or proc lasso. Addons that set their own Affinity should be allowed to do so in their own way and not interfered with after they started by task manager or proc lasso style programs.

 

There's no great gobs of performance to be lost or gained with the right AM, maybe only 5% in some cases. Certainly 2% or 3% going HT enabled at least. So it's a little bit of work to get the best out of it. The big problems to run into with the AMs improperly configured, are heat and VAS. But HT enabled always makes more heat as it does more work.

[GSalden 4,656]

Steve, when is it better to use 340 ( 00,01,01,01,01,00 ) and when better is it better to use 1360 ( 01,01,01,01,00,00 ) ...?

[SteveW 1,792]

Try both, they are identical but subtle differences depend on system resources. 340 can result in slightly more bandwidth to the system resources (less overall to the sim) when there's a lot of activity.

[GSalden 4,656]

Thanks Steve.

Will try both..

[Gemelli 0]

HT Enabled yes, but whether you can get more out of 5 LPs 1364=(01,01,01,01,01,00) over 4 LPs 1360=(01,01,01,01,00,00) is doubtful and uses more VAS. On top of that 1364 (5 LPs) also gives less room for the other stuff running, only one spare core, but 1360 has two spare cores.

 

For the 6 core HT enabled, I would try 1360=(01,01,01,01,00,00) with the cfg, and put exe addons on 2698=(10,10,10,00,11,10)=A8A or 4046=(11,11,11,00,11,10)=FCE with a .bat or proc lasso. Addons that set their own Affinity should be allowed to do so in their own way and not interfered with after they started by task manager or proc lasso style programs.

 

There's no great gobs of performance to be lost or gained with the right AM, maybe only 5% in some cases. Certainly 2% or 3% going HT enabled at least. So it's a little bit of work to get the best out of it. The big problems to run into with the AMs improperly configured, are heat and VAS. But HT enabled always makes more heat as it does more work.

allright il try this thanks for help

[R Hardman 7]

 

 

For the 6 core HT enabled, I would try 1360=(01,01,01,01,00,00) with the cfg, and put exe addons on 2698=(10,10,10,00,11,10)=A8A or 4046=(11,11,11,00,11,10)=FCE with a .bat or proc lasso. Addons that set their own Affinity should be allowed to do so in their own way and not interfered with after they started by task manager or proc lasso style programs.

 

For some reason if I set ProATC on 2698=(10,10,10,00,11,10)=A8A or 4046=(11,11,11,00,11,10)=FCE the all sounds from this addon becomes intermittent and garbled. If I remove all AM's associated with ProATC it sounds fine. Weird.