Knowledgebase: Active Sky Next
Temporary Freezes with FSX
Posted by Jordan Jafferjee, Last modified by Robert Halmich on 03 September 2020 01:21 AM


Related Product: Active Sky Next, Active Sky 2016 - Related Version: ALL




Also known as the "8-minute freeze", this can occur intermittently during a longer flight.  When the freeze occurs, all motion on the simulator stops.  Sound may be observed still playing, but the FS program stops responding.  Approximately 8 minutes later, the simulator "comes back" and operates normally.



With much research and testing, HiFi has determined that this freeze is related to the threading, affinity and the collision and deadlocking of terrain load fiber processes within FSX.  It is almost unanimously related to use of Hyper-Threading, and can affect any FSX installation, including default/stock installations without any add-ons.  Use of weather add-ons increase the likelihood of this freeze.


Since this issue can be made worse when using Active Sky, although it is an FSX problem not directly related to our product, we provide potential solutions below to help anyone experiencing these freezes:


1) Use an appropriate AFFINITYMASK setting within your FSX.cfg configuration file.  This setting specifies which cores are used for FSX.  Using too many cores, or improper cores can cause freezes.  If you are using 6 or more cores, it is important to limit the cores used, as too many cores causes synchronization problems and more potential freezes.  We recommend using 3 cores maximum, regardless of HT enabled or not.


2) ASN will warn and optionally apply an appropriate AFFINITYMASK setting if it is not already configured.  The setting used will be based on using up to 3 physical cores, but depends on your CPU and number of cores, and if HT is enabled or not.




4) Use lower resolution cloud textures and setting your Cloud Draw Distance to 90 or less.


5) Lock frame rate lower - try setting to no more than 30.


6) Update video drivers.


7) Run FSX in compatibility mode for win 7 (if using win 8 or above).


8) Disable SLI if activated. 


9) Make sure you are running the latest version of Active Sky ( .



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