Further reading (benchmark/results thread): http://forums.bistud...ead.php?t=88629
Since I have bought ARMA 2 a few month ago, I was unhappy with the performance of the game. Besides ample hardware power (i7 @ 4Ghz, 12GB DDR-12800, GTX280 Hydro Copper, 2 Vertex 120GB SSD in RAID0, etc.) I was suffering rather low frame rates and - more annoying - stutter and texture LOD trashing.
I have done a crazy amount of testing to find a solution to these problems, and now have finally reached a stage where I am happy with the results, which I want to share.
All these tests were done on 1920x1200 resolution (both 3d and display), and with 3000m view distance and everything on very high, and post processing off.
1) Selecting the best OS
I have tried Win7 in 64bit/32bit, Vista in 64/32 bit, and XP in 64bit/32bit. In terms of performance, ARMA 2 works best with XP32 - here's the ranking (from good to bad):
1) XP 32bit
2) XP 64bit
3) Win7 64bit and 32bit (no big difference)
4) Vista 64bit and 32bit (no big difference)
ARMA 2 seems to make no use of the increased capabilities of an x64 bit OS - it is a pure 32bit application. Running a 32bit application in a 64bit Windows in theory should not cause significant performance hits (thanks to WOW64), but in case of ARMA2, it does actually cause issues. This is most true for what I call the "smoothness" of the game: In 32bit, there was less stutter (i.e. if you make a 360 degree turn, it was a smooth turn without hiccups).
In terms of framerates, XP beats all other Windows versions, and 32 bit comes out best.
Stutter was also least apparent with both XP versions, and best with the 32 bit version.
No difference was found in my testing in terms of texture/LOD trashing - in all cases, after some minutes of gameplay, textures would visibly pop when you move fast, which I found very annoying.
Which leads me to my second point.
2) RAM disk
I wanted to find out what the reason for the texture trashing is. Do narrow down the problem, I monitored memory and disk usage during gameplay.
To make a very long story short: the hard disk is a major culprit here, as there is ~8GB of data and textures that is getting streamed as you move around the game. Both the occasional "Hiccup" as well as texture popping happen when ARMA 2 starts to stream from disk.
To solve the problem, I created an 8.5 GB RAM disk with SuperSpeed RamDisk plus (there is a 14 days trial version. The reason I chose this software over others is that is can adress the memory space above 4GB on 32 bit systems, it supports auto save/load of the RamDisk so it is persistent, and supports large RamDisks).
I then moved the whole ARMA 2 folder (Steam Version) into the RamDisk (please note that you have to start ARMA 2 using the arma2.exe within the moved directory. Alternatively, you can create a symlink to the folder - pls google it).
The result was - for the first time - a smooth game experience. It is hard to describe, but without all the stutter and texture popping, the game reaches a new level in perceived visual quality. Everything is smooth, LOD's draw instantly, and the whole game play feels a lot more fluent. For the first time, I feel happy with the performance of ARMA 2.
Let me know if you have any questions, and pls try it out yourself and share some of your results if you want !
Edited by qwertz, 30 March 2014 - 11:31 AM.