Explanation - Performance degradation Alaska

[LuisFelizTirado 33]

Some users will have noticed that performance degrades with Alaska, particularly in densely-wooded forests and in Anchorage.

 

Please note that this is not due to anything in Alaska that is different from Hawai'i. Rather, the last title update changed the way the target framerate is set. Here is the explanation from a member of the MGS team:

 

From our tests, Alaska performance tends to be the same as Hawaii. Of course mileage on different hardware may vary. The title update did change how we try to manage framerate when v-sync is on, and depending on your system, this can make things better or worse.

 

Previously we only measured CPU frame time when trying to set a target framerate, but if you end up having a slow GPU, or you are heavily CPU bound, it would try to render too fast. It also accounted for some of the jittering when v-sync was on because we weren't maintaining a constant display rate to the screen.

 

Now, frame rate will drop down to the next lower integer divisor of your monitor refresh. For example if your monitor is 60Hz and you get an average of 45 FPS, the game will run at 30FPS to make sure that it can consistently hit every other v-blank. Normally even though the frame rate is lower in this situation it actually looks smoother. However if your average is just barely above 30, Flight may bounce between 20 and 30 fps, and that could end up slightly worse experience than previously.

 

Determining which setting has the most impact can be difficult because it depends heavily on whether you are CPU bound or GPU bound. It is not always straightforward to figure this out, but one general approach I use is to look in task manager at CPU usage on the primary core. If it is 90% or higher, it is possible you are CPU bound. You can also look at the GPU activity in the Catalyst control center, or nVidia control panel to see how close to 100% they are. I'm sure there are other programs that can display this info too.

 

 

So, in principle, even if framerates are halved in certain situations now, performance should be smoother overall and the degradation may be less noticeable than before.

 

Best regards.

Luis

[dburne 2]

Interesting, thanks for sharing the info.

 

So far I msyelf see no performance degradation at all on my system with Alaska and the title update, very smooth.

[Mirtma 0]

Good to know. I was asking myself why is flying over Alaska so choppy. Mostly over forests. Is there any tip what could I do to get previous performance back?

[jcomm 5,939]

Hi Luis,

 

thx for forwarding this precious info.

 

I myself have noticed no performance degradation at all, either with VSync or without it, but I am not using the maximum settings, and my CPU is underclocked (I'm an underclock nuts....). I might try it at full graphics settings and with my ASUS set for "Turbo Mode"...

 

I thought I experienced mild stuttering in Hawaii when there were many trees, but now in Alaska, and even with lot's of them and the animations, I have no impact on fps :-)

[scotchegg 4,186]

I noticed some fps hit but turning off v-sync got rid of it.