Skyrim Acceleration layer

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maboblivion

[H]ard|Gawd
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This was on the front page yesterday of [h]

http://www.joystiq.com/2011/12/27/skyrim-pc-mod-claims-to-improve-performance/


So after trying it.... :D It works pretty well in cpu bound places. Like at the top of
Dragon reach looking down at the tree. Gives 5 to 10 fps in some places and even
under 20 fps seems smoother.

It's incredible the difference just optimizing the code can do.

edit: Other better , faster option is skyboost
edit2 : Beta patch 1.4 from Bethesda out

http://forums.bethsoft.com/topic/1325462-skyboost-topic-2/
 
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I was going to try that mod last night but didn't have time. I did manage to improve my performance by disabling crossfire though... (damn amd drivers.. lol)

I'll give this thing a try tonight. I play at 1920x1080, 4xaa (no fxaa) and Ultra settings.
 
Majinhoju said:
I was going to try that mod last night but didn't have time. I did manage to improve my performance by disabling crossfire though... (damn amd drivers.. lol)

I'll give this thing a try tonight. I play at 1920x1080, 4xaa (no fxaa) and Ultra settings.
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What drivers are you using? Try the 12.1 preview drivers with no CAP installed. I get excellent Crossfire scaling with one monitor (doesn't work worth a shit in Eyefinity, though).
 
Parja said:
What drivers are you using? Try the 12.1 preview drivers with no CAP installed. I get excellent Crossfire scaling with one monitor (doesn't work worth a shit in Eyefinity, though).
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I was thinking of trying those, but never got around to it, haha.

I'm using 11.12 with the latest caps which is likely the reason for the negative crossfire scaling. I'll try the preview drivers soon (hopefully tonight) and I'll let you know if I have any success. Thanks for the suggestion :)
 
Well I updated to the 290.53 drivers and did notice less stuttering in heavily CPU bound area's where FPS dips. After enabling the script extender (acceleration layer), I noticed a 5 FPS boost in heavily stuttering area's. Definitely recommend everyone picking this up!
 
The creators comment on it is telling...

works mostly by rewriting some x87 FPU code and inlining a whole ton of useless getter functions along the critical paths because the developers at Bethesda, for some reason, compiled the game without using any of the optimization flags for release builds
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"for some reason", huh?

*cough*
console port
*cough*

Eh, at least it's still a great game, even if performance does tend to be much worse than it should be for the visual quality.
 
I've been using it for the past 5 or 6 hours worth of gaming (out of about 33 hours total). The game seems less stable using acceleration layer to me.

Framerate is certainly higher in areas of high CPU usage like cities, but on the flip side I've experienced stutter more frequently (where the game pauses or stutters even though framerate remains high) and also the game has crashed to desktop a couple of times in the past 5 or 6 hours of using the acceleration layer, something that didn't happen at all in the previous 26 or 27 hours of playing (the game crashed a couple of times previously while alt+tabbing, but never just while the game itself was running).

Maybe that's why Bethesda themselves didn't implement it, QA issues with it.
 
i installed it and was ready to do testing, then played LoL all night lol

will check it out tonight, hopefully.

I did test out the new nvidia beta drivers (290.53) and didn't notice any difference whatsoever :(

I tried forcing performance AO, and it took away 10 fps which was too much when i'm 30-60 outdoors and 15-30 in cities.
 
@Tudz - I suppose that's not entirely surprising. Making second-guesses about what the app is trying to do based on watching it run is...haphazard at best.

From comments people who have read through his code (and the author's) made:

It replaces many calls to functions that would have been inlined if the compiler optimizer settings were set to something higher than "off" with actual inline code that nicely fits in the five bytes the jump instruction was previously taking up. It also overwrites several functions, replacing them with SSE implementations instead of the very painfully slow original x87 implementations.
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My guess after reading the code for this engine over a long period of time (oblivion -> fallout 3 -> new vegas -> skyrim) is that at some point they got hit by a compiler bug, then used the "nuclear option" with the optimization settings. This happened across several projects, and now we have something that insists on storing the 'this' pointer on the stack and reloading it every time it's needed. (that's bad)
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it does have an uncountable amount of obviously uninlined functions that do nothing but e.g. "return *this", which are called thousands of times a second. It's instantly visible in the top 10 list when running TESV in any code profiler.
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They'd just have to add the string "/O2 /GL" to their Makefile. They simply didn't compile the code with the optimizing compiler switches. I'd also recommend to use something else than msvcrt for the math stuff, but just by compiling it as optimized code would at least double the total execution speed, resolving a lot of slowdowns without any additional investment of effort on Bethesda's side.
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...just sounds like really, really sloppy code.

I mean, gods know, I've done that, myself, for quick plugins I needed to knock out in a hurry. Hit a compile error with an optimization flag on, turning it off fixes it...well, hey, I didn't really need that flag, anyway...performance isn't an issue for this...just remove it and move on.

That can hardly be said to be true of Skyrim - a tier 1, multi-million-dollar, major release. When you get a compile error...you fix the compile error, not take a shortcut.
 
Yeah, Alexander helped fix an error in the first fix by Arisu and then someone needed it to work on windows8 beta so they kinda split. Hopefuly that won't hamper the optimization effort.
 
I really thought they needed to move on from the Gamebyro engine because it was so outdated and had the same problems for so long. When it became clear that skyrim was using a heavily modified version of Gamebyro, I gave them a bit of a break, assuming they overhauled the problem areas, which I think they actually did pretty well. After all, they've been using it for so long that I figured they must know it damned well at this point, and in all fairness, what they did produce is pretty damned impressive. Still, hearing that they probably just disabled compiler optimization because couldn't get it working properly, and hearing about how horribly inefficient a lot of the code is (I'm no expert but frequently used functions that are smaller than the overhead of a function call not being inlined is just blatantly bad), I now REALLY think they need to pick up a new engine.

Edit:
Quick question of anyone who's knowledgeable about these things. How does this acceleration layer actually modify Skyrim? I think I get how the d3d9.dll changes work, but I assume that the d3d9.dll code is available to be modified and recompiled and as far as I'm aware, this isn't an option for skyrim.exe. I won't try and expand on what I do/don't know anymore, but any insight would be appreciated.
 
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Tudz said:
I've been using it for the past 5 or 6 hours worth of gaming (out of about 33 hours total). The game seems less stable using acceleration layer to me.

Framerate is certainly higher in areas of high CPU usage like cities, but on the flip side I've experienced stutter more frequently (where the game pauses or stutters even though framerate remains high) and also the game has crashed to desktop a couple of times in the past 5 or 6 hours of using the acceleration layer, something that didn't happen at all in the previous 26 or 27 hours of playing (the game crashed a couple of times previously while alt+tabbing, but never just while the game itself was running).

Maybe that's why Bethesda themselves didn't implement it, QA issues with it.
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hmm.. i might hold off then. I'm content with my performance and would gladly sacrifice a few frames to avoid any crashes. If the 12.1 preview drivers work as intended, then my crossfired 6870s should have enough horsepower to add some oomph to my performance. :D
 
I played with it for a few hours and didn't crash at all.

Some ppl put mods like the FxAA injector and changed some settings in the ini that might cause the crashing or black screens.
It's quite safe, try it and at worst all you need to do is launch it via the normal steam launcher instead of the skse exe.
 
Yeah just give it a try, don't let my experience put you off, maybe you'll have more luck than me ;) I have also modified the ini with higher uGrids and grass draw distance... but I modified those long before I tried Acceleration Layer and never had any problems in the 20+ hours I was using them.
 
If I don't like it is it easy to remove? Hopefully without having to reinstall the game :p

If so, I'll give it a try.
 
Majinhoju said:
If I don't like it is it easy to remove? Hopefully without having to reinstall the game :p

If so, I'll give it a try.
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If I understood correctly, you can always just ignore it and start the game normally, as for this mod to work you have to start it with SKSE_Loader, a script extender which has its own plugins that this mod belongs to?
 
Yes that is indeed how u launch it ,through the skse loader. I've compared between the two by quitting the game and alternating between the normal launcher and skse loader without any trouble.
Made a shortcut on my desktop and renamed it without any trouble.
 
Was dubious about this at first, but then decided to give it a go. Makes a huge difference.

Especially in cities where it did stutter some. Marketh where you got the waterfalls and mill it use to be annoyingly stuttery, totally fixed now. Nice frame rate boost.

Ran the console command GETSKSEVersion to confirm I wasn't imagining things.
 
What i like is that even when it drops in the 20's stays smooth , and water keeps flowing smoothly and no drop frames. I had to to OC to get stable frames at the settings i was running , now its playable without oc tho i think i'll still oc 1.8ghz on my rig is just 2 slow to push my video card.
 
yea i switched from SKSE to Skyboost R2 and i prefer Skyboost, with my setup SKSE plugin gave me 1-2 fps Skyboost R2 gave me 8 more on top of that. enough so that i could force 8192 shadow size and maintain 25+ fps
 
crazyeyesreaper said:
yea i switched from SKSE to Skyboost R2 and i prefer Skyboost, with my setup SKSE plugin gave me 1-2 fps Skyboost R2 gave me 8 more on top of that. enough so that i could force 8192 shadow size and maintain 25+ fps
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Just so you know, R3 has been released which might give you a few more FPS over R2.
 
The buggy state of this game at launch, on top of the obvious lack of optimizations done, demonstrated by these mods, really shows that Bethesda doesn't give a fuck other than shoehorning a game out the door.
 
bigdogchris said:
The buggy state of this game at launch, on top of the obvious lack of optimizations done, demonstrated by these mods, really shows that Bethesda doesn't give a fuck other than shoehorning a game out the door.
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You expected more from Bethesda?
 
Crash250f said:
Still, hearing that they probably just disabled compiler optimization because couldn't get it working properly, and hearing about how horribly inefficient a lot of the code is (I'm no expert but frequently used functions that are smaller than the overhead of a function call not being inlined is just blatantly bad), I now REALLY think they need to pick up a new engine.
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unfortunately that doesnt work as well as it seems in theory. the people who create stinker code in the first place just create more stinker code when they start over.
 
If it stutters too much try SKSE xD ... he's talking bout trying to do sse4 instruction next....
darn my cpu does only sse3 doh!
 
bigdogchris said:
The buggy state of this game at launch, on top of the obvious lack of optimizations done, demonstrated by these mods, really shows that Bethesda doesn't give a fuck other than shoehorning a game out the door.
Click to expand...

Maybe a part of the problem is they set a release date so far ahead of time and weren't able to get the game to an acceptable level before release, so just threw out the best version that had been through QA rather than delaying the release.
 
Nice. Standing still after loading the game in town, my frame rate was 40, after installing skyboost it's running at 50 at the very same spot. I haven't even updated my graphic drivers yet. If I can get crossfire to run on this game, it'll run niiiiiice :)
 
OK here are my results now that I've tested both Skyrim Acceleration Layer (SKSE) and Sky Boost R3

Sky Boost = HOLY @#)$#*@!

I have a 2500k OCed to 4.4ghz. I found a heavily CPU bound area, which was as soon as you enter the Whiterun front gates and are staring at the building that's just to the left (which is across from your home). I disabled VSYNC both in INI and in the CP. I'm using a blend of Ultra settings with ugrids @ 7 and some shadow tweaks.

With no acceleration I was at 40 FPS
With SKSE AL I was at 40 FPS. (other area's though i've found this gives me a 5-6 FPS boost *VERIFIED*)
With Sky Boost R3 - 60 FPS. That's a 20 FPS gain. Whiterun was absolutely buttery smooth as I could possible want!
I also went to Riften and Markarth and the FPS was butter @ 60 FPS. I'm absolutely floored at how much more smooth this game is now.

I absolutely recommend Skyboost R3 over the SKSE Acceleration Layer mod. Plus with Sky Boost you don't need to run a separate executable.
 
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Yeah, I put on SkyBoost, and looking down from Dragon's Reach I went from 35 fps to 48 fps. Pretty impressive. Hopefully it doesn't screw anything up.
 
People who installed skyboost , can u report on how fluid it is...... are the frames choppy?
or is it smooth when moving in towns and outside ?
 
maboblivion said:
People who installed skyboost , can u report on how fluid it is...... are the frames choppy?
or is it smooth when moving in towns and outside ?
Click to expand...
The mod is incredible. Grab the R3 version and drop the two files into your Skyrim data folder. The biggest improvement to me was inside towns (Whiterun/Riften/Markarth). I gained 20 FPS in all three and it's very smooth now. Keep in mind my CPU is @ 4.4 ghz so folks with slower CPU's may not notice as much of a gain.
 
I oc to 3.1ghz c2d 6320 , was asking cause some ppl felt skyboost had higher frames but less smooth. Guess i'll check it out and report as well :p
 
bigdogchris said:
The mod is incredible. Grab the R3 version and drop the two files into your Skyrim data folder. The biggest improvement to me was inside towns (Whiterun/Riften/Markarth). I gained 20 FPS in all three and it's very smooth now. Keep in mind my CPU is @ 4.4 ghz so folks with slower CPU's may not notice as much of a gain.
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Into the base Skyrim folder, not the Skyrim\data folder, unless it works from either location. Documentation says Skyrim folder, and that's where mine seems to work.
 
Forceman said:
Into the base Skyrim folder, not the Skyrim\data folder, unless it works from either location. Documentation says Skyrim folder, and that's where mine seems to work.
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Yes exactly; into the folder that contains TESV.exe and SkyrimLauncher.exe. If you put it into your \Data folder it will not work.
 
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