observation about the possible cause of stutter/micro lag

[twistking]

Hello,

i made a very interesting observation about DCS (vanilla, stable on steam) performance, that maybe helpful to improve performace, especially concerning micro-lag.

 

My system has a SSD for the system and two HDD. The HDD are western digital "blue" 1 TB each, while the first is a newer model, faster on paper with big cache and second is a slightly older model. Both HDD are in good condition, file transfers are very fast and i use both hdd on a regualr basis without problems.

Rest of the system: i7-860 (overclocked), 8gb ram, gtx 770, windows 10

 

I used to have DCS on the second HDD, which on paper, should be slightly slower. Some days i decided to try the new steam feature to move the installation to the other drive, hoping for a minimal performance gain from the newer HDD with the bigger chache.

However that move, introduced stuttering or micro-lag to the game. Every minute or so, the game would freeze for a very, very short amount of time. Also the loading times were noticebly longer.

The freeze seemed not related to real-tiem caching, because it even happened on a otherweise empty map when just slowly cycling above a small area. complex missions, with many units and for example flying slow and fast has still good fps, but the same micro lags from tiem to time.

 

i searched the forum and noticed that stuttering seems to be a problem for soem people and i read about one person, who got rid of the stutter when disconnecting a drive that was not even in any way related to the dcs install.

 

so i decided to move dcs back to the "slower" HDD and the stutter and mciro lag was completely gone. also the game is loading faster again.

 

as mentioned before, both HDD are in good condition. they are responsive and perform as expected for other games and data transfers. they are not fragmented. they are only 50% or less filled. page file is (windows stadard) on the system SSD only.

system itself seems to be in good shape with 0%-0,1% cpu load on idle and plenty of free ram for dcs.

 

also from my experience the mciro-lag were way to short to be explained through system limitation. (they were no lower fps going with the micro-lags, but decent fps (30fps in extreme conditions up to well above 100), so i suspect it is some problems with the game code, maybe memory allocation or something.

 

maybe my observation is helpful for the devs to iron out performance issues. with dcs back on the "slower" drive i now get very good performance, without any stuttering and low fps only in very extreme situations, which is somewhat expected on my somewhat old hardware.

[DirkLarien]

Interesting

Can you give precise specifics of said discs ?

 

S.M.A.R.T. perhaps ?

[twistking]

the older drive is a WD BLUE "WD10EALX-009BA0"

the newer one, which introduced the stutter, is a WD BLUE "WD10EZEX-75M2NA0"

I ran a S.M.A.R.T. test and a proprietary "WD lifeguard diagnostics quick test" on each drive and both drives passed both tests.

 

The controller is in AHCI mode. I'm not sure though what s-ata spec it is running. Since the the pc is some years old now, it might only be s-ata 2??

 

More importantly i don't have any other "issue" with the drive and the fact, that the stutter is (was) completely independent from mission complexity and therefore general fps and ram usage, makes me believe, that it could be some weird bug in the game code.

 

*edit* i was referring to the newer disk as the "faster" one. however, to be honest, i could not really tell, and never tested if it was indeed faster. it is newer though and like the "older" one it always performed as one would expected from a 7200rpm hdd.

longer loading times and the annoying stutter in DCS being the only exception.

Edited January 31, 2017 by twistking

[AtaliaA1]

That is an interesting observation.

 

What Motherboard are you using? Although it is possible that code is a factor one would rule out, I am thinking a Motherboard controller issue is another possibility in this case.

 

My system isn't far from yours. I use an Asus I can't remember the name of it right now. Point being I haven't had any issues with FPS/Stuttering in almost any ver. of the Sim. Once I needed to patch it but it cleared it up.

[twistking]

i think it is this one...

https://us.msi.com/Motherboard/P55CD53

 

yes, i also think it might be hardware-related to some extend. when i think about it, also another game i have on the drive loads a bit slower than one could expect. i never expected any stutter though even with "big" and heavy-data-streaming games like arma 3 and gta4. file transfer seem fine and i also use the drive for professional video editing from time to time and always felt it performed well within the limits of magnetic storage. as mentioned above, SMART and a proprietary self-check were fine.

 

i have wonderful performance with DCS on the other HDD, so i thought, that maybe it is not a real bug but the incapability of the engine to cope with a very specific, yet unkown, system/driver/controller/drive/protocoll... set-up. So, i agree with you that it could very well be a hardware issue (controller etc.), but it only showing in DCS and not (notably) in any other usage scenario also hints towards the software not adapting well to specific - perhaps unexpected - hardware "peculiarities".

 

i would just have called it a day and would happily play dcs on the other HDD, but did post this, because i am aware that there are other people, who have or have had problems with stutter and micro-lag.