What were the Quad Core FSX.CFG settings?

[Turnip]

I can't locate the thread that has info on the FSX.CFG info for dual and quad core. If I remember right, we had to make the OS see the cores or something like that. I just put in a Q6600.

I have the

[JOBSCHEDULER]

AffinityMask=14

put in there.

[Matthew Webb]

You'll find the info you need in either your AU Gold or Blue manuals.

Basically AffinityMask=14 tells FSX to use cores 2,3 and 4 only.  1 is left for all the running OS and background programs.

Check this thread to find FSX.CFG - or consult the manual.

http://orbxsystems.com/forums/index.php?topic=1365.0

Cheers,

Matt.

[Turnip]

Thx Matt. 

[Matthew Webb]

Too easy.

[jgruschow]

Try changing the 14 to 15.

This will keep Windows etc on core #0

[Turnip]

Oh!  14 doesn't do it?

[squeeker]

There's a "core 0"? I thought there was 1, 2, 3 and 4. Now I'm really confused. What's the downside to setting AffinityMask=15 over 14?

I only know what I've learned through the forum so be gentle..

[Matthew Webb]

A bit more explanation.  The number it sets it to is in binary.  4 binary numbers has a max of 15 decimal, when counting from zero.  So this number can cover all possible combinations of 0 or 1 for 4 processes.

FSX's main processes will (unfortunately) always use the 1st core available from the chosen cores.  So if you have a value of 14 = 0111, FSX's main process will always run on the 2nd and use 3 and 4 for other processes.  The main point here is that FSX's main process needs as much dedicated CPU as it can.  Hence using the value 14 will guarantee that FSX will always have a whole core to itself and where possible other processes will be offloaded to core 3 and 4.

Now if you have a value of 15 = 1111 (like me) FSX.exe will run on the 1st core, sharing it with all the OS processes and anything else you're running.  

I use a program call AlacrityPC that will shutdown any processes and services that I don't need when flying.  I also run my FSX utilities on my wife's PC.  Note that windows will (unfortunately) always run on the 1st core, there's nothing that can be done to change that.  Once my PC is shutdown to bare minimum, FSX is pretty happy on the 1st core.

http://blogs.msdn.com/ptaylor/archive/2007/05/15/new-tweaks-in-sp1.aspx

EDIT:  In the link above, it has the following:

7  = 3 cores

Never use this value.  The blog is only demonstrating the mathematics of the value, not its proper usage.  Using a value of 7 will have FSX run on the 1st 3 cores only, leaving the last core with absolutely nothing to do and FSX sharing the 1st core with the OS! 

Cheers,

Matt.

[Matthew Webb]

There's a "core 0"? I thought there was 1, 2, 3 and 4. Now I'm really confused. What's the downside to setting AffinityMask=15 over 14?

I only know what I've learned through the forum so be gentle..

It depends on your point of view.  I count 1, 2, 3, 4 for processors.  jgruschow in his post is counting 0,1,2,3...   I see where he is coming from.  Sometimes I reckon kids should learn to count from 0 to 9, not 1 to 10  .  Especially in this digital age!!!

[squeeker]

Thanks for the explanation Matt. Very clear. That makes perfect sense. Cheers, Steve.

[Gurdy]

A bit more explanation.  The number it sets it to is in binary.  4 binary numbers has a max of 15 decimal, when counting from zero.  So this number can cover all possible combinations of 0 or 1 for 4 processes.

FSX's main processes will (unfortunately) always use the 1st core available from the chosen cores.  So if you have a value of 14 = 0111, FSX's main process will always run on the 2nd and use 3 and 4 for other processes.  The main point here is that FSX's main process needs as much dedicated CPU as it can.  Hence using the value 14 will guarantee that FSX will always have a whole core to itself and where possible other processes will be offloaded to core 3 and 4.

Now if you have a value of 15 = 1111 (like me) FSX.exe will run on the 1st core, sharing it with all the OS processes and anything else you're running. 

I use a program call AlacrityPC that will shutdown any processes and services that I don't need when flying.  I also run my FSX utilities on my wife's PC.  Note that windows will (unfortunately) always run on the 1st core, there's nothing that can be done to change that.  Once my PC is shutdown to bare minimum, FSX is pretty happy on the 1st core.

http://blogs.msdn.com/ptaylor/archive/2007/05/15/new-tweaks-in-sp1.aspx

EDIT:  In the link above, it has the following:

7  = 3 cores

Never use this value.  The blog is only demonstrating the mathematics of the value, not its proper usage.  Using a value of 7 will have FSX run on the 1st 3 cores only, leaving the last core with absolutely nothing to do and FSX sharing the 1st core with the OS! 

Cheers,

Matt.

So it is reversed? I mean 14 =1110 in binary and 7 = 0111, the cores are numbered in reverse ?

[Matthew Webb]

So it is reversed? I mean 14 =1110 in binary and 7 = 0111, the cores are numbered in reverse ?

That's right.  7 will use cores 1, 2 and 3.  14 will use 2, 3 and 4.  In binary, 111 (or 0111) is 7, 1110 is 14.

http://en.wikipedia.org/wiki/Binary_numeral_system

Cheers,

Matt.

[Turnip]

Uh... OK  so I change it to 15 making XP run on the first core only ( Core 0). Then FSX, Radar Contact etc runs on the second, third and fourth core ( Core 1,2 and 3).

Is that right?

They drug me kicking and screaming into the 21st century!

[Wolter van der Spoel]

No Turnip,

Set affinity to 14 so fsx uses core 1, 2, 3 and other applications use core 0, if you set it to 15, fsX will use all 4 cores and you could get lockups because to much stuff will need to be handled by the 0 core

[macca22au]

Turnip, your OS will run on Core 0 whatever you do.  Therefore the idea is to get FSX off Core 0  (yes I know, it really is the first core but in computer numbering the cores are numbered 0,1,2,3). Because the threading in FSX is pretty minimal, I assign the Affinity for Active Sky X (look for X-engine in the list of running applications in Task Manager) to Core 3.  You can do that with your extras as well.  Stay away from Core 1 as in theory that is where the bulk of FSX is being processed.

I did read somewhere that FSX will use Core 0 whatever we say, but I am following the technical leaders in this forum in blind faith.

[Turnip]

OK  Thanks for 'esplainin' it again. I had it right the first time. 

[jgruschow]

No Turnip,

Set affinity to 14 so fsx uses core 1, 2, 3 and other applications use core 0, if you set it to 15, fsX will use all 4 cores and you could get lockups because to much stuff will need to be handled by the 0 core

Interesting Wolter. The reason I use 15 is to make fsx use all four cores.In practice #0 is normally at 100%  #1 and 3 about 40% and core 2 is about 10% higher than them. I find this works well and as yet I have not had any lockups.

I suspect, in reality, it doesn't realy matter. fsx will always use what's available. 14 should at least keep it separate from the OS

[Matthew Webb]

Interesting Wolter. The reason I use 15 is to make fsx use all four cores.In practice #0 is normally at 100%  #1 and 3 about 40% and core 2 is about 10% higher than them. I find this works well and as yet I have not had any lockups.

I suspect, in reality, it doesn't realy matter. fsx will always use what's available. 14 should at least keep it separate from the OS

It's really a matter of personal taste and system configuration.  For me, I lock my FPS to 25 and get that when my Affinity setting is either 14 or 15.  When I'm not running FSX at all, my 1st core is hardly doing anything when using AlacrityPC.  Since I run ActiveSky, etc on a different PC, my first core virtually does nothing.  So for me, using 15 makes sense.

If other tasks are eating more CPU, you are getting lockups or stutters 14 is probably the best for you, since it looks like FSX is fighting for more CPU with other processes.  Check out your Task Manager to see what's going on....

Like Jack, I don't like seeing my 1st core doing next to nothing.

Cheers,

Matt.

[jgruschow]

Just did a little experimenting. Shifted to 14.

Now my #0 core is running at 2/5% load. Number 1 core 100% and 2 & 3 both about 80%.

All ths does is to make 3 cores do the work that 3 1/2 cores was doing.

I run fsx at maximum settings so I reckon I should give it all the available room.

As an aside. My comp is overclocked 20% and is running at 3.6. Temp ranges from high 50's to low 60's so I reckon a 3.6 quad is what is needed to run fsx properly. Now I even get YMML looking something like it is supposed to.

Now off to shift back to 15

[Turnip]

Hmmmm    I'll try both and post my "mileage" here. Guess it wouldn't hurt to test it. Hell.... I've tried everything else in the book. LOL

[squeeker]

My results: Q6600 2.4 overclocked to 403MHz, 39 degrees C, 4mb cheap 800MHz ram.

Scenery and autogen maxed out. Lightbloom on. Water low 2.x

9-12fps both cases (not configured as I would normally fly)

Changing affinity setting made no appreciable difference to frame rates or refresh times.

[Gurdy]

I guess the real advantage of running with cores 1,2,3 is that by default other applications like ASX and RC4 will run on core 0. It just allows  FSX to not to have to share CPU cycles with other apps.

Steve, try those same FPS tests running a couple of addons (if you have) and see if there is a markable difference.. I would be interested to know...

[jgruschow]

I guess the real advantage of running with cores 1,2,3 is that by default other applications like ASX and RC4 will run on core 0. It just allows  FSX to not to have to share CPU cycles with other apps.

Steve, try those same FPS tests running a couple of addons (if you have) and see if there is a markable difference.. I would be interested to know...

Addons make very little recordable difference. Ditto for running processes. Unless you are running right on the borderline you will gain nothing.

Same with fps. Locking them at 20 or so makes no difference. In fact fsx seems to run smoother with frames on full bore.

[squeeker]

Yep, no noticeable difference with photoshop going in the background, an extra couple of firefox windows going and FSinn. Maybe lost 1fps. No change in the speed the landscape was drawing...

[Turnip]

Nice information. I'm at 15 now and will try it with RC4 to see what effect. My rural flying is great now. Around Sydney, fast movers get a little choppy tho.

[Braedon King]

You can have as many applications (like PS, PSP, etc) 'running' in the background, and have no effect on CPU utilisation.  Why?  They are not using any processor cycles when you are doing nothing with them. They do however chew up RAM, which is more of an issue if you don't have enough, but not the subject of this post.

If task manager shows no CPU activity for a process, closing it should have no effect on FSX CPU utilisation other than the processor occasionally testing to see if the app wants to interrupt (a poofteenth of CPU% to do that).  Same with background processes.  Close them and free up memory, but unless the OS is actively using them (in which case it's probably not a good idea to shut it down), stopping them will free up memory, but should have little effect on CPU availability.  Doing all these tweaks really only plays in the 2% CPU utilisation that you see when the machine is idle, and most of that 2% is running the process that collects the processor stats and displays them for you (ie. you can't measure something without affecting the measurement).

cheers

Bungo

[Turnip]

POOFTENTH?    LOL, Now THAT'S one I've never heard of. Must be part of that computer nerd longo. 

[Gurdy]

POOFTENTH?    LOL, Now THAT'S one I've never heard of. Must be part of that computer nerd longo. 

Please Turnip my man, calling us nerds is like calling a turnip a carrot. It is GEEKs ...LOL

Oh and geeks are today what the girls love....  ;D ;D

[Turnip]

Got that right!