EFSA and EFSA+M: ExpandedFSAffinity

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EFSA and EFSA+M: ExpandedFSAffinity

Postby Steve Waite » Mon Apr 24, 2017 2:29 pm

Ideal Flight comes with Expanded Affinity in the base product. This allows the Windows jobscheduler to target lesser used cores outside of the simulator affinity to run simulator sub-processes across all cores.

With Special Edition and Professional versions from Flight 1, an improvement to EFSA is included: EFSA+M expanded affinity control.


In the following picture a test harness is used to create near identical runs of P3D. The top shows ExpandedFSAffinity enabled on an HT core, where the very clear improvement of up to 4fps is seen, not only that but the scenario loads in 6 seconds less time. These two graphs are the worst cases from several repeated tests. ExpandedFSAffinity improves the utilisation of Hyperthreading for P3D v2/3. The test involves multiple screens and windows with High settings AI controlled add-in aircraft and other objects to increase stress:


EFSA+M, "Expanded FS Affinity Masking", instructs the sim to truly run on more than four cores unimpeded by other processes and over-multiplied sim thread jobs. Expands the possibilities of the simulator application affinity.

Users of 6 or more cores will be able to gain most benefit from EFSA+M. EFSA+M is a product of codelegend research and development. Users with less cores can start the sim across many cores and corral them onto less cores to intensify work done.

An expert example shown here; we can use IF10 (SE or Pro) to start the sim main process on a core where we want, as we may have a faster setting for one core on the motherboard when overclocking:


Performance depends on simulator configurations. Some circumstances can yield bigger improvement than others. An example with thunderstorms added processing from lightening strikes can be seen to appear on +M cores where normally there is a spike of processing within the starting simulator affinity.


Set EFSA=True

6 core HT enabled:
1360=01,01,01,01,00,00=FSAM - 4 cores 5,4,3,2
1372=01,01,01,01,11,00=EFSA+M - 5 cores 5,43,2 + 1, adds core 1 to the sim for sub-processing
Put all addons on core 0, (00,11)

8 core HT enabled:
21760=01,01,01,01,00,00,00,00=FSAM - 4 cores 7,6,5,4
22000=01,01,01,01,11,11,00,00=EFSA+M - 6 cores 7,6,5,4 + 3,2, adds cores 2 and 3 for sub-processing
Distribute all addon exes on cores 1,0 - (high activity 11,01), (high 11,10), (low 11,00)

Please remember that results vary depending on scenario and other factors such as GPU setup and addon exes used and affinity settings on those. However, generally setting EFSA and EFSA+M will result in important improvements in overall sim throughput most of the time.

Prepar3D v3.2 load spreading without disturbing the four main sim jobs. In the lower half of the image, the addition of one +M core (LP0) shows the load reduced on the second sim job on core 2, LP 4:


Example scenarios with 6 core HT enabled 3960x+GTX680, showing ratings of +5% on P3D and +10% on FSX:

Prepar3D v3.2 medium settings:

Prepar3D v3.2 low settings:

FSX boxed edition medium settings:

Last bumped by Steve Waite on Mon Apr 24, 2017 2:29 pm.
software architect at codelegend.com
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