Difference between revisions of "Howto:Using additional OSG Pager Threads"

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you can configure OSG to use additional pager threads, which basically means the terrain cache gets additional CPUs it can use.
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You can speed up scenery loading times by configuring OSG to use additional pager threads, which basically means the terrain cache gets additional CPU cores it can use.
see the OSG docs, it's just an environment variable, i.e. something like OSG_NUM_DATABASE_THREADS
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See the OSG docs. To use additional threads just configure the following [[Environment variables|environment variable]] setting: <code>OSG_NUM_DATABASE_THREADS</code>. For a 4 core system try setting this to 2 or 3 or higher. For a 6-8 core CPU try increasing further to use extra cores. Try reloading scenery via the debug menu to see benefits - look at the CPU utilisation.
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This has the potential to speed up loading of scenery like [[OSM2City]]. People on the forum have reported instability. This will ''not increase FPS'', merely improve loading times - which will only be visible in areas with a lot of scenery objects.
  
 
Note that according to findings shared by Richard, when testing the database pager extensively (running with 20 DB pager threads), the main problem is the way that random objects (buildings, vegetation) are inserted into the scene graph doesn't seem to be compatible with lots of pager threads<ref>https://forum.flightgear.org/viewtopic.php?f=17&t=38094&hilit=pager+threads&start=15#p374620</ref>
 
Note that according to findings shared by Richard, when testing the database pager extensively (running with 20 DB pager threads), the main problem is the way that random objects (buildings, vegetation) are inserted into the scene graph doesn't seem to be compatible with lots of pager threads<ref>https://forum.flightgear.org/viewtopic.php?f=17&t=38094&hilit=pager+threads&start=15#p374620</ref>
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== References ==
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{{Appendix}}
  
[[Category:Core development]]
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[[Category:Multicore]]
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[[Category:Environment variables]]

Latest revision as of 13:54, 26 May 2021

This article is a stub. You can help the wiki by expanding it.

You can speed up scenery loading times by configuring OSG to use additional pager threads, which basically means the terrain cache gets additional CPU cores it can use.

See the OSG docs. To use additional threads just configure the following environment variable setting: OSG_NUM_DATABASE_THREADS. For a 4 core system try setting this to 2 or 3 or higher. For a 6-8 core CPU try increasing further to use extra cores. Try reloading scenery via the debug menu to see benefits - look at the CPU utilisation.

This has the potential to speed up loading of scenery like OSM2City. People on the forum have reported instability. This will not increase FPS, merely improve loading times - which will only be visible in areas with a lot of scenery objects.

Note that according to findings shared by Richard, when testing the database pager extensively (running with 20 DB pager threads), the main problem is the way that random objects (buildings, vegetation) are inserted into the scene graph doesn't seem to be compatible with lots of pager threads[1]

References

References