Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Robert, Problem solved! It appears that this was either a Vista issue, an Nvidia Vista driver issue, or a combination of both. I managed to get an XP installation running using an extra internal hard drive on the 4 monitor system. With osgviewer on 4 monitors I'm getting nearly 500 fps with vsync off (and with vsync on, I'm getting a constant 60 fps). ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Joe, This has to be driver/OS issue, and all you'll be doing on the OSG side is characterising this problem, you won't find a magic fix on the OSG side that will fix this. The only thing left that you could try is to implement the swap groups extensions in osgViewer. This is just a long shot though. I do think it's time to go talk to NVidia about the set up, they might be able to give you a heads up on what to expect. Robert. On Tue, Oct 28, 2008 at 8:53 PM, Joe Lyga <[EMAIL PROTECTED]> wrote: > Hi again, > > I tried fiddling with OSG_SERIALIZE_DRAW_DISPATCH, but it's not having > any effect. > > Anyway, I was able to duplicate the results I've been getting with my > program by just running osgviewer with a simple 3d arrow model (with > vsync off). (Monitors 1 and 2 are hooked up to the first graphics > card, and monitors 3 and 4 are hooked up to the second graphics card.) > > The first configuration I tried was running osgviewer full screen on > all four monitors. The framerate varies between 30 and 40 fps, and > notice the inconsistent frame markings and large draw time. > > > Second, I tried running osgviewer in a window and dragging it across > the first two monitors. The framerate jumps way up to over 1000 fps. > > > After that, I moved the same window over to monitors 3 and 4. The > framerate dropped way down to around 45 fps. > > > Moving that window back to monitors 1 and 2 made it jump back up to > over 1000 fps. > > After dragging the window over to monitors 3 and 4 again, I went into > display properties and disabled monitors 1 and 2. The framerate of > the window jumped up to over 1000 fps. > > > This is very strange. It seems like the second graphics card is > waiting on the first. Shouldn't they be running asynchronously? > > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Joe, OK this screenshot makes more sense... and is indeed how one would typically drive multiple monitors with the OSG. One optimization that is worth doing with this type of setup is use one graphics context per graphics card, and split the each window across two displays. This typically provides the best performance. But... other posts on similar about Visita/XP suggest that XP is capable of this, but Visita has lots this capability, which sucks. Linux is capable of doing the one context driving two screens, so if can port then you have a solution there. The only other thing you can try on the OSG side is to change the draw dispatch serialization flag to off, as right now its on by default. Use the env var OSG_SERIALIZE_DRAW_DISPATCH set to OFF, then run your app. In theory one should always have OSG_SERIALIZE_DRAW_DISPATCH set to OFF, but in my own testing have found PC OGL drivers/hardware perform worse when you allow multiple threads driving multiple cards to all do draw dispatch in a parallel, perhaps later drivers might fix/hardware this lack of scalability. I'd recommend that you do a search on this env on the osg-users archives to see the points I've raised in the past on this topic. In your case I don't actually expect the draw serialization to make a difference to you only getting fps, as the swap buffers aren't serialized - they all still run in parallel, and your not breaking frame due to draw dispatch anyway. What may help is the swap groups extension - it shouldn't be necessary to get 60fps, but perhaps the driver is just a bit crappy and needs the extra push to do the right thing. Robert. On Tue, Oct 28, 2008 at 5:40 PM, Joe Lyga <[EMAIL PROTECTED]> wrote: > Hi Robert, > > I guess I forgot to mention what the original problem was. Normally, the > program is run across all four monitors. However, even with practically > nothing loaded in view, I'm only getting around 30 fps. I was running it > independently on two monitors at a time in order to isolate the problem, and > there's definitely a difference between the first two and the second two. > Here is the stats of it running on four monitors, but I don't think it shows > as much as the stats with it on two each at a time. > > > > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Joe, Just looking at the two images, it really looks like you running two separate viewers. Is this right? Is it even two separate applications? The OSG allows you to run a single viewer across multiple contexts and this is the usual way that OSG users will do multi-monitors. Is there a reason why you are using this approach? Robert. On Tue, Oct 28, 2008 at 5:14 PM, Joe Lyga <[EMAIL PROTECTED]> wrote: > Hi again, > > I'm not having much success getting other operating systems to run correctly > on my vista machine. Windows XP doesn't support running off external drives > (and hacking it to work is a difficult process), and the latest Ubuntu live > cd I tried didn't have the correct nvidia graphics drivers. > > Anyway, I took a look at nvidia swap groups extension Robert mentioned. I > believe that synchronization between the graphics cards is something I'm > trying to avoid. Both graphics cards should be running independently. I'm > no expert, but judging by what I've seen so far and by looking at the stats > with vsync off, the second graphics card is waiting on the first. Could it > be that the second graphics card is trying to synchronize itself somehow > with the first graphics card? > > I reattached the stats with vsync off (first image = first graphics card, > second image = second graphics card) > Notice the inconsistant placement of the frame markers and the large amount > of empty space in the second image as opposed to the smooth performance of > the first. > > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Robert, I'll look into the Nvidia swap groups extensions. Unfortunately, I'm stuck with Vista since it is a custom machine under warranty. I'll try loading up a linux live cd to see if I can produce similar results with osg-viewer. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Yes, with one monitor hooked up to each graphics card I'm still getting the same effect. The same goes with one monitor hooked up to the first and two on the second. However, if I only have monitors hooked up to the second graphics card, then the performance is as good as when I'm running it on just the first graphics card monitors. On Fri, Oct 24, 2008 at 4:56 AM, David Spilling <[EMAIL PROTECTED]>wrote: > Joe, > > Just out of interest, do you get the same issue with just one monitor > connected to each graphics card? ( I'm interested because I _think_ I get > something similar in this configuration, but it might be a separate issue). > I have the same setup as you (dual 8800, VIsta, etc.) > > Are you running dwm/Aero? > > David > > > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Joe, Just out of interest, do you get the same issue with just one monitor connected to each graphics card? ( I'm interested because I _think_ I get something similar in this configuration, but it might be a separate issue). I have the same setup as you (dual 8800, VIsta, etc.) Are you running dwm/Aero? David ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Joe, I don't personally have any vista machines so I can't test this, or vouche for how well multiple graphics cards will work under Vista, others have got it work, but I don't know whether this includes frame drops. From your description it does sound like a driver issue. Perhaps use the NVidia swap groups extensions might help solve this. What I can say is that I've got a linux system with two graphics cards and four monitors working on linux with good performance and not hiccups like you explain. So you could just dual boot your machine and do a sanity test. Robert. On Thu, Oct 23, 2008 at 10:15 PM, Joe Lyga <[EMAIL PROTECTED]> wrote: > Thanks for the response Robert, > > I turned V-sync on, and I took some screenshots with the program running > full screen. The first image is with the program running on the first or > second monitor (hooked up to the first graphics card), and the second image > is with the program running on the third or fourth monitor (hooked up to the > second graphics card). All 4 monitors are set to the same resolution and > refresh rate. > > > I'm not sure how much it's showing up in the stats, but the program running > on the third or fourth monitors is noticeably choppy. The frame markers are > also in an inconsistent pattern, not always occuring every 16.67 ms vsync. > When I'm watching the stats interactively, they appear to be very jumpy. > When the program is running on either of the monitors hooked up to the first > graphics card, there appears to be a steady 16.67 frame. > > Any advice? > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] choppiness on 2nd graphics card with 4 monitors
Hi Joe, This sounds like a driver issue. Could you please try enabling vsync, as then you will get a better picture of the load balancing in a usage model that end users should be using. Robert. On Wed, Oct 22, 2008 at 5:39 PM, Joe Lyga <[EMAIL PROTECTED]> wrote: > I'm having an issue with a program that I'm working on that uses OSG. I > have a machine running windows vista that has two Geforce 8800 GTX graphics > cards. I'm running these cards with SLI disabled so I can hook up 4 > monitors, with 2 on each graphics card. In display properties, I have > monitor 1 (hooked up to the first graphics card) set as the primary monitor, > and the windows desktop extended onto the other 3. > > Anyway, when I'm running this program in windowed mode on the first or > second monitors (which are hooked up to the first graphics card), I'm > getting a good framerate (around 600 fps) with smooth motion. If I simply > drag the window to the third or fourth monitors (which are hooked up to the > second graphics card), the framerate drops to around 100 fps and the motion > becomes choppy. I took some screenshots of the stats on both. The first > image is with the program running on monitors connected to the first > graphics card, and the second is on monitors connected to the second > graphics card. > > One thing I tried was disabling the two monitors hooked up to the first > graphics card (by setting the windows desktop to not extend onto these two > monitors). As a result, trying to run the program running in a window on > monitors 3 or 4 (hooked up to the second graphics card) gave a good > framerate without any choppiness. > > I've been trying to figure out what's been causing the choppiness with > running the program on monitors connected to the second graphics card. Does > anyone have any experience with running multiple monitors on multiple > graphics cards? > ___ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
