[INVESTIGATING]PRELOADING BUGGED & FPS PROBLEMS

[Gryzor]

I think the fps stuttering or low performance could be related the a 2.5.6 introduced bug regarding incorrect preloading of terrain or something similar.

 

Look at SU-25T instant mission over caucasus: every time targeting is switched on, a huge stuttering and fps happens, specially when the nose camera is oriented towards horizon. Normally, fps goes down a bit with targeting, but not a such huge (30-40 reduction in fps).

 

The same happens with oters sensor in A-10A, A-10C;

 

If fact, I modified preloading config in options.lua, to this:

 

["preloadRadius"] = 0

 

That modification, putting to 0, in older versions did remove the preloading limit, causing a huge impact in performance and filling all VRAM.

Now, in 2.5.6, performance is the same with preloading = 0, in comparison with others values. Same stuttering, same low fps, etc... so I think that lower performance in 2.5.6 could be related to having preloading option disabled, the sims tends to preload everything (subsequently, stutterfest happens).

 

I hope 2.5.6 performance will be, at least, the same performance we have in 2.5.5,

 

Maybe preloading issues could be related also with F14 low performance in RIO when WCS is on (radar must "preload" all scenery, maybe???)

Edited February 15, 2020 by Gryzor

[RealDCSpilot]

Interesting find, might be worth looking into it for ED.

[RealDCSpilot]

@Gryzor

 

Congrats! I think you found it! I just checked my VRAM usage and it is totally out of control. Even a 2080ti doesn't have the belly for it. So a VRAM memory leak is causing all the troubles...

[BIGNEWY]

Thanks we are looking into VRAM use

[Gryzor]

In my experience the performance is similar in previous version when I disabled preloading (with editing of "["preloadRadius"] = 0".

 

VRAM totally out of control (2080ti). I bet 2 cents that It could be related with high load times we have now.

[Hippo]

Thanks we are looking into VRAM use

 

 

On a Sunday? For goodness sake, go home to your families - it's only a game.

[BIGNEWY]

On a Sunday? For goodness sake, go home to your families - it's only a game.

 

Dont worry, we will make time for family :)

 

Thanks

[Gryzor]

In addition, just to add to the thread: when you input CTRL + PAUSE to show FPS and other data used in sim, VRAM Ram usage shows everytime a "0" value. Maybe it could be related.

[RealDCSpilot]

Another addition, if you choose to fly the Ka-50 (the oldest and simplest cockpit model) with DCS 2.5.6 in PG for instance, VRAM usage doesn't fill up over 100%. It's still quite high, but doesn't overshoot and performance is ok when flying over Dubai. Every aircraft with the latest and most detailed cockpit fidelity, especially the F-16, leads to VRAM overflow and tremendous performance hits.

[Worrazen]

@Gryzor

 

Congrats! I think you found it! I just checked my VRAM usage and it is totally out of control. Even a 2080ti doesn't have the belly for it. So a VRAM memory leak is causing all the troubles...

 

Can you post some actual data please?

 

Use GPU-Z or Rivatuner statistics server with MSI Afterburner overlays and create a video of the cases you think are too resource hoggy.

[Eldur]

Probably the issue for my excessive version of that issue as well, hooves crossed

[Worrazen]

Why don't we first ask if the OP meets minimum requirements of a (mid-to-high range) SSD for DCS? Because the preloading thing has kinda been over with ever since SSDs are the standard for DCS, at least I have no issue.

 

(Remember, cheap SSDs can be worse than HDDs)

[marcwoolery]

Why change in the LUA there is a setting in options for Preload Radius NO ?

A lot of speculation, can you provide hard numbers ? Is VRAM the Page file ? please define acronyms.

[marcwoolery]

Why change in the LUA there is a setting in options for Preload Radius NO ?

A lot of speculation, can you provide hard numbers ? Is VRAM the Page file ? please define acronyms. BTW - what is the solution, defining the problem is of no use without a solution... always fun to speculate though. SSD (drive) ?

Seems gamer reviews have shown that SSD hi speed and all dont make that big a difference. Are we sure that SSD's are critical to DCS ?

Edited September 17, 2020 by marcwoolery

[RedeyeStorm]

Not for me. I have it on a normal HD. It does matter with loading speed off course but no difference during play. Must say I never had issues with stutters or such.

[Worrazen]

Why change in the LUA there is a setting in options for Preload Radius NO ?

A lot of speculation, can you provide hard numbers ? Is VRAM the Page file ? please define acronyms. BTW - what is the solution, defining the problem is of no use without a solution... always fun to speculate though. SSD (drive) ?

Seems gamer reviews have shown that SSD hi speed and all dont make that big a difference. Are we sure that SSD's are critical to DCS ?

 

SSD does help with some of the stuttering, however, you are right, stuttering shouldn't really happen even on a HDD, stutter as in an engine-freeze until the data is loaded, the game should load all it's data necessary for a fluid gameplay experience with 16 GB or above RAM, and only then the speed of your textures popping in would be determined by your storage speed, so with HDD, you'd just be looking at low LODs and it would take time to transition to a higher quality LOD, there should technically be no stuttering.

 

It's not really textures anyway, with the diagnostic software I've seen time and time again that parts of assets (objects, etc) are being lazy-loaded later right when the engine needs them, not everything is being properly loaded to RAM at mission load. The fix isn't that easy as new things get added to the sim all the time. I guess tracking every single file / groups isn't that straight forward, that's why a smart new approach to memory management is probably being developed. Also perhaps this is a bug an only happens on some machines, but you can see how a fast SSD would make these stutters much less visible, kinda shadowing the issue with brute force, that's what I said back then, okay we'll deal with it with bruteforce just move to SSD and it'll be fixed properly later.

 

Those acronyms are are pretty much standard across the industry, nothing to do with DCS. I'm really not having a luxury of 2 hours on explaining the windows memory/terminology stuff right now.

Edited September 19, 2020 by Worrazen

[Taz1004]

I did this while making my mod but seems to help so this is what I do.

 

In vfstextures, unzip and rezip everything using "Store" or "No compression". Using 7zip or Winzip. Mission that took 15 seconds to load was reduced to 13 seconds. At the cost of disk space. I have DCS on M2 drive so benefit may be minimal but may be more helpful on HDD.

 

I've also rezip terrain mods with "No compression"

 

You can just do it on the biggest zip files or keep a copy of the No compression versions so you can copy them back after an update or repair.