Re: [osg-users] Framedrops in paged terrain databases windows XP
Hi Ralf, what is the Vertical sync setting for your video card/application? It should be On if you don't want database pager thread to affect framerate. Best, Marcin Ralf Stokholm pisze: Hi List I have been fighting a studdering problem in my application for a while, my best guess at the moment is tht the problem is relatet to paging of large terrains. We are using a large terrain build using virtual planet builder. To test the behavior of this model i load it in osgviewer and I notice the same drops here, to get some better data on this i modified the stats class so that it will also collect max times for the various tasks, and changed it to show frame time and not FPS. I load the model in the viewer so that it is set up to strech across my two screens 1920x1200 and 1920x1080. I rarely see a frametime average above 10 ms, but when I experience the drops I have seen max frametimes as high as 160 ms. The connections seams to be with the last draw call that will increase its max time as high as 150 ms. So I guess my question is what could make my last draw reach so high, is the interaction with the database pager part of this draw? I have tried many different settings for the env values for the database pager, but although they make a difference on performance it dosent seam to affect the random framedrop. Im running on windows XP, core2 quad 3 Ghz 4 BG mem, terrain is running of a 2 TB raid 0 drive and I have a Nvidia GTX 280 graphics card. osg is version 2.6.1 Brgs Ralf Stokholm http://arenalogic.eu/air_combat_trainer.aspx ___ 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] Framedrops in paged terrain databases windows XP
Hi Ralf, On Mon, Dec 15, 2008 at 1:02 PM, Robert Osfield robert.osfi...@gmail.com wrote: It just so happens I'm currently working on making the new scheme the default setting for the DatabasePager. The next dev release will have this in place. The new defaults are now checked in to svn/trunk. Robert. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Framedrops in paged terrain databases windows XP
Hi Robert Thanks for the swift answer. Will investigate some more and maby check out the new pager options once we get past our delivery in two days :-) Marcin How would not enabling vsync affect the pager? again framerate is not a problem its the extremely long frames we are seeing from time to time. Brgs. Ralf Stokholm www.arenalogic.com 2008/12/15 Robert Osfield robert.osfi...@gmail.com Hi Ralf, Frame drops like this are very likely down to either the OS's virtual memory being utilized or memory down on the GPU hitting a limit. I would had thought that frame drops are unlikely to down to the database pager itself, although it's management of memory may well be exacerbating the situation by not expiry subgraphs quick enough for their memory to be reused thus keeping the overall memory consumption below tollerable limits. The DatabasePager has lots of work done to it since 2.6.1, much of it in the area of expiry of subgraph and in particular there is new scheme that works to cap the total number of PagedLOD that are loaded in to memory, with the later 2.7.x dev releases and svn/trunk you can enable this new mode by setting the env var OSG_MAX_PAGEDLOD to a value such 500, the lower the value to lower you memory usage will be, but the less data will be kept in memory so that you revisit a region it won't be cached. It just so happens I'm currently working on making the new scheme the default setting for the DatabasePager. The next dev release will have this in place. Robert. On Mon, Dec 15, 2008 at 12:37 PM, Ralf Stokholm alfma...@arenalogic.com wrote: Hi List I have been fighting a studdering problem in my application for a while, my best guess at the moment is tht the problem is relatet to paging of large terrains. We are using a large terrain build using virtual planet builder. To test the behavior of this model i load it in osgviewer and I notice the same drops here, to get some better data on this i modified the stats class so that it will also collect max times for the various tasks, and changed it to show frame time and not FPS. I load the model in the viewer so that it is set up to strech across my two screens 1920x1200 and 1920x1080. I rarely see a frametime average above 10 ms, but when I experience the drops I have seen max frametimes as high as 160 ms. The connections seams to be with the last draw call that will increase its max time as high as 150 ms. So I guess my question is what could make my last draw reach so high, is the interaction with the database pager part of this draw? I have tried many different settings for the env values for the database pager, but although they make a difference on performance it dosent seam to affect the random framedrop. Im running on windows XP, core2 quad 3 Ghz 4 BG mem, terrain is running of a 2 TB raid 0 drive and I have a Nvidia GTX 280 graphics card. osg is version 2.6.1 Brgs Ralf Stokholm http://arenalogic.eu/air_combat_trainer.aspx ___ 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 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Framedrops in paged terrain databases windows XP
Hi Ralf, On Mon, Dec 15, 2008 at 2:28 PM, Ralf Stokholm alfma...@arenalogic.com wrote: Will investigate some more and maby check out the new pager options once we get past our delivery in two days :-) The new DatabasePager may well be the solution to your problem. You could grab just the DatabasePager header and .cpp from the svn reposotory and use it in your local OSG version if you don't wish experimenting with a whole new release upprade. How would not enabling vsync affect the pager? again framerate is not a problem its the extremely long frames we are seeing from time to time. I think Marcin answer in FAQ sytle, not having vysnc enabled will lead to a far less stable frame rate and paging will just exacerbate this, vsync enabled irons out the framerate and lowers the CPU utilisation giving it more time to page and get data merged. This is an entry level error when doing vis-sim/game dev, so is worthy of explaining for new developers. In your case the problem likely lies elsewhere. Robert. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Framedrops in paged terrain databases windows XP
Hi Ralf, Frame drops like this are very likely down to either the OS's virtual memory being utilized or memory down on the GPU hitting a limit. I would had thought that frame drops are unlikely to down to the database pager itself, although it's management of memory may well be exacerbating the situation by not expiry subgraphs quick enough for their memory to be reused thus keeping the overall memory consumption below tollerable limits. The DatabasePager has lots of work done to it since 2.6.1, much of it in the area of expiry of subgraph and in particular there is new scheme that works to cap the total number of PagedLOD that are loaded in to memory, with the later 2.7.x dev releases and svn/trunk you can enable this new mode by setting the env var OSG_MAX_PAGEDLOD to a value such 500, the lower the value to lower you memory usage will be, but the less data will be kept in memory so that you revisit a region it won't be cached. It just so happens I'm currently working on making the new scheme the default setting for the DatabasePager. The next dev release will have this in place. Robert. On Mon, Dec 15, 2008 at 12:37 PM, Ralf Stokholm alfma...@arenalogic.com wrote: Hi List I have been fighting a studdering problem in my application for a while, my best guess at the moment is tht the problem is relatet to paging of large terrains. We are using a large terrain build using virtual planet builder. To test the behavior of this model i load it in osgviewer and I notice the same drops here, to get some better data on this i modified the stats class so that it will also collect max times for the various tasks, and changed it to show frame time and not FPS. I load the model in the viewer so that it is set up to strech across my two screens 1920x1200 and 1920x1080. I rarely see a frametime average above 10 ms, but when I experience the drops I have seen max frametimes as high as 160 ms. The connections seams to be with the last draw call that will increase its max time as high as 150 ms. So I guess my question is what could make my last draw reach so high, is the interaction with the database pager part of this draw? I have tried many different settings for the env values for the database pager, but although they make a difference on performance it dosent seam to affect the random framedrop. Im running on windows XP, core2 quad 3 Ghz 4 BG mem, terrain is running of a 2 TB raid 0 drive and I have a Nvidia GTX 280 graphics card. osg is version 2.6.1 Brgs Ralf Stokholm http://arenalogic.eu/air_combat_trainer.aspx ___ 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
