Here are 2 quotes from Adam, verbatim:"FIBER_FRAME_TIME_FRACTION determines the maximum amount of time per frame that we will run fiber jobs on the primary thread. We measure how long it took to simulate and render and then multiply that time by FIBER_FRAME_TIME_FRACTION to determine how long to run the fibers. For example, if it took 10 milliseconds to simulate and render and FIBER_FRAME_TIME_FRACTION was set to the default value of 0.33, then we would allow the fibers on the primary thread to run for up to 10 * 0.33 = 3.3 milliseconds. For fraction values of 1.0 and 2.0, the time given to fibers would be 10 milliseconds and 20 milliseconds, respectively.The operation of FIBER_FRAME_TIME_FRACTION on single core machines has not changed since RTM. On multi-core machines, we moved many fiber jobs off of the primary thread and onto secondary threads. Since FIBER_FRAME_TIME_FRACTION only affects scheduling of jobs on the primary thread, it will have less of an impact on the performance of Flight Sim on multi-core machines. In fact, we moved so many jobs off of the primary thread that there probably isn

Wow, excellent info, thanks!One question, though-- might those of use with multi-cores benefit by *lowering* this value? Or will the engine simple complete all available texture work and not use up its allotment anyway?EDIT: Oops, didn't read carefully enough-- it looks like he already answered that. But it still seems that lowering this value could help because it could take some of the "burstiness" out of the work by spreading it across more frames, thereby guaranteeing the CPU has more resources available for other types of work.Any estimate just how much of the texture work is done on secondary threads? For example, if more than half is done on secondary threads I might consider setting the value to .15-- that would give my CPU 15% more resources in textures loading situations, but still load textures about as fast as with RTM, correct?

Thank you for the detailed answer.In fact the performance problems with this FS9 code path had me pulling my hair for a while. It *is* an I/O hog.

Yup, and unfortunately the way the FSX texture path works,it doesnt serve your needs. A fix for that, though, is for a future version. I am not saying FS11, just not in any patch.

I should point out that Adam is talking about behavior in SP1, not the released FSX.Yes, after you install SP1, if you have a dual-core machine, you may benefit from actually lowering the value to something like 0.15.

The quick and positive response from users, and the wide-ranging potential it suggests, seems to warrant consideration. But you already know that.

>I should point out that Adam is talking about behavior in>SP1, not the released FSX.Yup, I realize that.>Yes, after you install SP1, if you have a dual-core machine,>you may benefit from actually lowering the value to something>like 0.15.cool, thanks!

On my main simming machine (a Dual Athlon rig with Geforce 7800 GS 4xAGP) the 2.0 settings brings frame rates down into the single digit range.Although it is nice to fly at 100 knots with textures below the aircraft mostly crisp, these frame rates are no good for me.I think I'll be back to a setting below 1.0Christian

Locking the frame rate does not appear work correctly with the fiber setting at the extreme value of 2.0. Anything but "unlimited" results in low frame rate.Setting to "unlimited" gives me high FPS (25-30). Setting to anything but "unlimited" gives me about 10 FPS.