I use Process Lasso myself and noticed a lot of threads popping up on how to use it. I'm no advocate for the program but I decided to make a how to since there isn't much variation from system to system.

 

 

1) Download Process Lasso or buy it (paid version allows you to save configurations)

 

 

2) Set an AM (Affinity Mask) for Prepar3d within the config file (this is critical, do not use Process Lasso to set the AM for P3D)

 

Consolidated the "smoothest" and most popular Affinity Masks values here :

 

4 core NO hyperthreading processors: 14 or 15 (If you decide to use 15 bear in mind that you will not have a core entirely free for addons)

 

4 core WITH hyperthreading processors : 84, 85, 116, 120  (same as above 85 will not give you an entire core free for other uses, however you will have an LP free)

 

Note: The general consensus is that P3D works best with 4 cores or logical processors at most, period. However if you have autogen settings maxed out and feel that you need more power you can use 174, 244, 248.

 

 

 

3) Start P3D, then Lasso. Find Prepar3d.exe under the 'Process name' column. You should see that under 'CPU affinity' P3D is using the correct cores assigned by you in the config file.

 

Now right-click the Prepar3d.exe process --> Priority class --> Always and chose High. You can select Realtime instead, but I personally do not see the need for it and it also prevents your Display from turning off during idle state. 

 

Next right-click Prepar3d.exe again and select 'Classify as a game'.

 

 

 

4) This is the tricky part. The AM you assigned to P3D tells it to use certain LPs/cores and not use the rest. Use an Affinity Mask calculator to find out which cores are not being used by P3D. There are plenty of guides/threads out there that teach you how to do this.

 

For this example I'm going to use an AM of 116. 116 in binary is (0010 1110). Which means the first 2 logical processors, "Cores" 0-1 are not being used by P3D. Take note of this. Yes I know Core 8 is also not being used but we do not need it for this example.

 

Now you need to launch all the external addons you plan to use with P3D. After doing so, find each of them in Process Lasso, right-click --> CPU affinity --> Always --> Select CPU affinity and now only select the cores not being used by P3D. For 116 that would be 0 and 1.

 

Do the same for all the addons you have. Take note, if you have several addons it might not be a good idea to assign all of them to the same 2 cores due to potential overloading issues.

 

For me personally, I have ASN, GSX and EZCA assigned to Cores 0-1 with Process Lasso.

 

That's it, you're good to go. Feel free to experiment with different Affinity Masks and configurations.

 

 

 

Abbreviations : 

 

HT : HyperThreading

LP : Logical Processor

AM: Affinity Mask

 

Tips:

 

Active sky next process name is : ASNext.exe

GSX process name is : couatl.exe

 

For simplicity's sake, most software refer to logical processors as cores, when in fact they are not. Bear this in mind to avoid confusion when setting configurations in Process Lasso. LP 0-8 is essentially Core 0-8 in their terms.

 

Depending on the AM you choose for P3D, if you only can afford to have an LP free instead of an entire core (2 LPs), you should limit each addon to one LP and try not to spread it out over different cores. In other words, only assign your addons to different LPs if they are from the same core. E.g. Core 0 = LP 1-2.

 

 

 

Hope I was clear enough and you guys find this useful.

 

Regards

Thank you for this great explanation, it copied and saved to my tips folder!

Thank you for this great explanation, it copied and saved to my tips folder!

 

Appreciate the gratitude! I was afraid it was too lengthy and complicated.

What I wonder: is it the huge effort worth? Do you have to repeat this process each time you start your flightsim session or are those affinity settings saved? Does Process Lasso start itself or can it be linked to Prepar3d.exe, meaning it only starts when this exe is executed? Sorry for those questions...

What I wonder: is it the huge effort worth? Do you have to repeat this process each time you start your flightsim session or are those affinity settings saved? Does Process Lasso start itself or can it be linked to Prepar3d.exe, meaning it only starts when this exe is executed? Sorry for those questions...

As far as I know, if you have the paid version all configs are saved.

 

Process Lasso can be set to start up with Windows. The example was for only the first time you start it up.

 

Most people I know who use lasso have not regretted it. I personally feel it is a worthwhile investment.