Ways to lower RAM usage?
CatinBag
Posts: 51
Ive been rendering on a 16 gb RAM computer so far but I recently picked up a cheap refurbished computer so I can have 2 running at once.
The new computer is a lot slower than my current one, but that was expected as it was dirt cheap. However, Ive never noticed just how much RAM renders take up until my new computer started spitting out errors on too much RAM usage when I try and render images. The current render I am running, when I tested on my current computer, took up 12 gb of RAM while rendering. My current system also has a 980ti (6 gb VRAM) I did not check how much VRAM was being used. So my question is, is there a way to lower the amount of RAM used while rendering?
Ive checked other fourm posts and the only answer I got was render it by parts and photoshop stitch them back together.
The render only has 4 figures (all gen 3s with irays) and a simple backdrop. I have seen other people's renders with a lot more figures than that. So how do they do it without running out of ram? Do you have to have like super beast computers with like 64 gb of ram or something?
Too Long; Didnt read:
Is there anyway of lowering the amount of RAM used without having to lower the amount of figures and objects in your scene?
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Comments
Usually the textures are what uses up a lot of RAM -- if there are figures that aren't being scene close up, you can make scaled-down copies of the texture .jpg's and use those instead. You can hide geometry that's not visible in the Scene pane -- if clothing covers most of the figure, set the body parts underneath to not visible.
You can reduce the size of the texture maps (diffuse, bump, trans, etc) in PS/GIMP - if your characters aren't that close to the camera, they don't need the full resolution in their texture maps. (Save with a different name / rename the originals so you don't lose anything)
Mouth closed? Remove the inner mouth maps completely
Iray uses about 3 bytes per pixel...so a 4096 x 4096 texture map will use close to 50 MB each...and each figure will have enough texture maps to push that number up to over half a GB.
And clothing can be very high.
Now, a 2048 x 2048 will use around 12 MB...or 1/4th the amount!
So your biggest savings will be in reducing the image sizes. Not saying hiding/removing 'extra' geometry won't help, but compared to the map reductions, you'll be hiding a lot of mesh data.
Thank you for your suggestions. I will give them a try
Try converting any figures (people etc) whom you have finished posing into props. This should significantly reduce the amount of memory they use, but you could not adjust the pose again. Best idea is to save the figure first as a sub-scene, so it can be reloaded should you need to adjust the pose.
Ok, by hiding the skin areas covered by clothing, I have managed to decrease my RAM usage by 40%.
I tried this, but when I do that, the clothing disappears. I googled but didnt find an answer. How did you fix that problem?
You need to convert the clothing to props aswell. There is a script which you can run that will convert a figure and all clothing/hair parented to it into props. The script can be found here:
http://docs.daz3d.com/doku.php/public/software/dazstudio/4/referenceguide/scripting/api_reference/samples/nodes/convert_figure_to_props/start
Look for displacement maps on surfaces and try removing them. I have yet to see displacement maps have any discenable effect in Iray without ballooning memory use. For objects/characters far away from the camera you might also try removing their normal maps.
When you start your render after the first iterartion is written out, cancel it but keep the render window open. In DAZ clear the scene by creating a new blank one then go back to the open render window and click resume. This frees up the memory from the viewport.
Eyes closed or facing away from thecamera, remove all maps. On figures that are not close to the camera, or on figures where only one is; make all figures share the same eye textures.
They may render in parts; figures in a scene may be split; I had the same issue with 7 figures and a backdrop; I rendered in two parts, each with four figures in the scene - I needed one to be in both as shadows might have looked odd. I could have rendered it three times and reduced figures more.
Use the same textures on figures can be a big help; slight variations can be achieved by tweaking the shaders slightly. The same texture on all or many figures can be an issue as characters can look more similar - or even too similar
..that's what I do (the latter that is). This way in large scenes if I have to change the pose or something else like a surface, I can do it without waiting forever.. I then substitute the newly posed character for the old one.
As to reducing texture size, I mentioned in the What Would You Like to See for Daz 5 thread that it would be nice to have the means to do that directly in the Daz programme as it would be much simpler rather than having use a 2D programme. There is already a means available to add levels of detail, it would be nice to be able to reduce them as well.
What about Texture Atlas?
Greetings,
Just picked up the Iray Memory Assistant, because I had exactly this problem a few days ago. It's out of its 60 day window, so you can get some decent deals on it now and then.
What I did was to
In the end, I got it under the 4GB limit for my video card, but it was rough.
I'm hoping the Iray Memory Assistant will make decisions easier, so I'll know in advance which of those things will have the biggest impact.
-- Morgan
with usage of connect i can rename textures but cannot use them with that new name
i get a warning then
Huh? One more reason not to use connect.
One solution is to rename the originals until you need them [torsomap -> torsomap2.jpg] - name the smaller maps with the original's name - then swap the names back when you need a larger map.
Alternatively - manually apply the new smaller maps in the surfaces tab ... that'd take a while in a large scene.
If you make reduced-size versions of the textures and the product is installed with Connect, don't keep the revised textures in the same folder, put them in your regular Runtime/Textures folder (e.g. under "My Library").
Why go and resize texture maps and replace them on a character on a scene by scene basis?
Wouldn't it just be easier to make some presets...let's say Sunny7 2K and 1K (or whatever) and then just use the presets when needed, instead of replacing them one at a time?
You can set up the presets before hand, just load the character/texture set you want to use. Resize your images (place them in their final destination, as this is the important part) then load them using by clicking on the little image (base color for example...).
Then repeat for all the image maps on the character. When finished, save as a material preset (something like Sunny 2K would be good).
If you are using a custom/tweaked skin...do this for that preset...or make a 'default' and a 'tweaked' version of the presets. Then it becomes a one time thing...just use this preset. It can even be done to characters in existing scenes without any trouble.
One thing I would do, though, after removing/replacing the textures is to resave the scene file and restart Studio, before rendering. That will completely clear any cached images from memory.
Same with removing the maps from inside the mouth...why not make a 'mapless' mouth material preset?
The attached duf is a simple Genesis 3 Mouth Blank, simply drop it in your Presets/Materials folder or other folder where you'll be able to find it. (I may upload a 'full set'...Genesis through Genesis 3 with icons). The trick when saving a Material Preset is to expand the surfaces in the save dialog and adjust by checking/unchecking what you want. Like if you don't want to change the UV set on the target, uncheck the UV items on the list. Otherwise the preset will switch the target to the UV set that was used by the source.
Iray Performance Tips
I wrote a script that works with ImageMagick to resize ALL images on the selected objects in a scene. It creates them in the same locations as the original texture images, and tackes on a "_med" and "_sm" before the file extension. It allows you to select whether to generate only medium (half-scale, 1/4 the pixels), small (quarter-scale, 1/16 the pixels), or both.
It also includes a script to allow you to change the selected images for selected objects in the scene (if they've been resized this way.) Just select which ones you want to change, then run the script, and select whether you want them to change to full, medium, or small textures. The script then adjusts them.
I just need to write up a good readme (to cover installing ImageMagick right) and find someplace to host it......
I'm currently rendering a G3F at mesh subdiv 3 with loads of HD morphs activated, 4k 16bit displacement maps, an underlying geometry shell with 4k displacement maps, displaced hair, loads of Garibaldi obj hair, a million+ poly Marvelous Designer dress with 4k 16bit displacement, four iray decals, and a 16k HDR lighting setup, on a machine with 12Gb of RAM. But I don't bother with GPU as almost nothing I do would fit on the majority of NVidia cards anyway. Are you sure your machine's disc swap space is set up to accomodate large memory's worth of graphics? One thing I also do religiously is go to the Task Manager and set Daz Studio's affinity to 6 threads rather than the default 8, which frees up a couple of threads for the system and makes even moving the mouse cursor around easier.
That script is something that would be a great addition to the tool kit. It should be able to be adapted to use something other than Imagemagik...tdlmake can do resizing, so calling that from within Studio should be able to substitute. I'm not sure if it would be of the same quality, though.
And Qt includes image resizing functions, so they should be available through scripting, too.
Although, it would probably be best as a full plugin.
As an alternative, you can use GIMP or PS in batch mode to reduce size of tons of images at one time. I love ImageMagick, I have to write scripts in Perl to do lots of image conversions for work but scripting isn't everyone's forte so using batch processing in editors like PS/GIMP is a good way to go if one does not script or code in an open source language but GIMP or Photoshop are readily available . I'm more of a GIMP fan so I use this method in GIMP to do batch resizing outside of ImageMagick if it's not available on the PC I'm using:
...it allows for reduction of texture resolution in programme? Everyone is telling me I have to do it in a 2D programme which can be very time consumiing if there are a number of texture files for the same item (particularly characters).
...but if you eliminate displacement maps how will you get the proper texture detail? This is an issue I have with Iray as surfaces that should have some roughness ot them often look unnaturally "smooth".
...yeah I'm in the same boat. I often tend to create very "busy" scenes that maybe would fit on a 16 GB Quadro P5000. I have my swap disk set to 22 GB and so far never had a render crash, just takes forever to complete as my system still has HDDs. Hoping to scrape up the extra cash for a Win7 Pro OEM so I can upgrade the memory to 24 GB (the W7 OEM costs more than the 24 GB tri channel kit). One of the big issues with Iray rendering is you need to keep th scenefile and Daz programme open which takes more processor and memory resources. One scene I have takes up a whopping 8.7 GB when uncompressed leaving me with about 2 GB for the render process so it almost always goes into swap mode, as after Windows and system utilities, there is only 10.7 GB of available memory left.
Anything other than closeups, you'll lose the detail, anyway...and mid/long shots, they don't do much of anything, except consume RAM. Unlike 3DL, Iray does not mipmap the textures and use a smaller resolution at a greater distance from the camera. That's what all the manual tweaking is about.
In general, at a distance of just a few feet, most people ARE 'smooth'...they also aren't very 'shiny'...so it should be more about controlling glossiness/specularity than 'details' on anything more than a couple of hundred units (cm) away from the camera. Of course going too much away from the sheen most characters have, you'll end up with the 'lightly baked' dead look.
...then why in my bus stop scene with teh two girls did the bricks of the near shelter, wall, the concrete of the trash bin, the road, and the sidewalk in the foreground look "correct" in 3DL but in Iray were totally flat and featureless? Likewise in the Streets of Old London, even though I changed the lighting mode removed hte puddles, and turned down the reflectivity used for making it look "wet" before converting, the road looked like a linoleum floor with a cobblestone pattern.
Before converting any 3DL shaders I always set the lighting model appropriate for the material as it is often set to "Plastic" by default. I also zero any ambient channels and remove reflection maps (even when rendering in 3DL) well as often those are more for the benefit of Poser's Firefly render engine.
"Lighting Model" is largely (or entirely) a matter of how the specularity interacts with lights and the other properties, Iray doesn't use specularity though the conversion will take account of the settings.
If the 3Delight materials relied solely on the displacement for relief then the Iray material, if there isn't enough mesh resolution for the dispalcement to work, will look flat as there won't be normal or bump maps to break that - you would need to use an external tool to get a nomral (ideally) or bump from the displacement, or at least use the displacement as a bump map. But you are right, the dsplacement will be visible until the scale of the relief it is generating drops to the pixel range (and may have an effect for longer than that depending on shading rate, with values less than 1 for shading rate each pixel will be sub-sampled and fine dispalcement may still influence the final colour of each result).
You have to be selective on the displacement removed. Displacement on skin for Genesis characters will disappear due to precision very quickly, displacement for brick and such are normally MUCH larger scales and will appear at longer distances. Iray also has issues with displacement... the subd must be VERY high for any displacement to be of any use. For Iray, you're better off using normal maps or bump rather than displacement.
Kendall
Dont' forget that it's possible to subdivide a mesh in DS using Loop or Binary algorithms, to avoid getting the rounded edges and corners that often happens with low rez props when using the Catmark subdiv algorithm. I much prefer using the mesh subdivision for displacement (G3F at 3 or 4), and setting the iray displacement subdiv to 1 at most. IIRC, using mesh subdiv rather than iray subdiv produces better displacement results. It also makes it easier to refine the subdiv rather than having to go into the Surfaces tab.