Build Release Notes: 08-29-2011

HPD ARX-01C – Now has all basic and fixed setups for all tracks used by this season’s series. Ford GT – Reduced braking power to allow more brake pedal travel. – Increased power steering strength to help with the heavy steering. – Increased front downforce by 10% to help limit nose light conditions, after re-analyzing wind tunnel data. – Now has all basic and fixed setups for all tracks used by this season’s series. Chevrolet Impala – Now has all basic setups for all tracks used by this season’s series. – During this season’s update a change was made that made older replays not play back properly. This has been fixed. Chevrolet Silverado – During this season’s update a change was made that made older replays not play back properly. This has been fixed. Simulation Performance Improvements There are two new memory related settings in the advanced graphics options, one related to GPU memory availability (video RAM) and the other related to CPU memory availability (system RAM). This change is intended to improve the simulation’s scalability, and to help address some of the current memory related performance issues in multi-class sessions. There is now a new performance meter which helps diagnose memory related issues. It is attached to the L/Q/S meters, and the new meter is named P for “page faults”. More information on this new meter follows. GPU Memory Setting The “available texture memory slider” is now “Max GPU memory to use”, and it now limits how much video memory the simulation will use total rather than how much it will use only for textures. If you have more than one GPU (SLI or Crossfire), set it to the smaller one’s memory capacity as resources are duplicated on each GPU. Max System Memory Working Set Setting The new “max system memory working set” setting has been added to the graphics options, below the GPU memory slider. It defaults to 1200 MB for systems that have 4 GB or more of system RAM, and 1000 MB for systems that have 2 GB or less. This setting controls (roughly) how much system memory the simulation will use at most. If you have a lot of RAM (4 GB or more) and never have performance issues, you may want to increase this limit a little bit from the default. See the Q&A section below. Page Fault Meter A page fault indicator, “(P)age Faults”, has been added to the (L)atency/(Q)uality/(S)kew meters. This new meter shows hard page faults and soft page faults as different colors. Hard Page faults are by far the worst type, and show up as green, yellow, or red, depending on how many are occurring per second. If you see temporary green/yellow/red spikes on this meter it is normal for most PCs. But, if you see constant levels of yellow or red page faults, you may be suffering from a lack of physical memory. To remedy the situation either lower the “max system memory working set” slider in the advanced graphics options to reduce the amount of memory required for the event (and restart the sim), or else it may help to add system RAM to your PC. This meter currently tops out red, at 30 hard page faults per second. A steady stream of even a few faults per second may slow the simulation down significantly as your disk drive is being used as system RAM, so they are to be avoided if possible. Soft page faults are indicated as a gray bar on the same “P” meter, and are not nearly as serious as hard page faults. However, they are displayed to you as a warning, as they may indicate that either the GPU memory slider, or the CPU working set slider is set too large. If you see a solid gray bar in the “P” meter, try to eliminate it via options, but if you can’t, don’t worry about it too much, it may be normal in some situations. Q. What do I set the GPU memory slider too? A. As a starting point, set it to your GPU’s memory. If you have SLI or crossfire, choose the smaller GPU’s memory as resources are duplicated on each GPU. If this setting is causing performance problems lower it slightly and retest. Q. In testing sessions my textures look fairly high-res but when I enter an on-line multi-class session some of the textures look very blurry? A. The two new memory settings cause this effect. When large tracks and/or more cars types are loaded in a session, more vertices are placed into both system memory and video memory, leaving less space for textures. The texture quality is automatically reduced to fit them into the remaining space. The limiting is necessary to avoid exceeding your PC’s capacity. Q. Cars and trackside objects look like I have them set to MED or LOW detail, but I checked, and they are still at HIGH detail in the options? A. If the current working set (for the track and cars) is predicted to be way over your specified limit during loading, the simulator may now skip loading the top levels-of-detail for some objects to help reduce the working set to make more room for textures. Q. I never have performance problems and after the update my textures look very blurry at some events. How do I make it how it used to be? A. You may be able to adjust your settings to reduce these effects. During the event, go to the advanced graphics settings and look at the reported load of video memory and system memory working set (next to the two new sliders) to determine which setting may be causing the issue: (A) Check the reported system working set load. If it is approaching the specified limit (within 200 MB or so) then it is likely this setting that is limiting the texture quality too much. You can try increasing the working set slider by 100 MB or so, and then restart the session. Do not raise this setting if it is not the limiting factor. If you start seeing a lot of page faults now on the new “P”age fault meter, or if your performance degrades, then you should probably reduce this setting. Raising this setting too high will result in performance loss, and often will result in page faults. We do not recommend setting this value above 1100 MB for systems with only 2 GB or memory or less. If you have 4 GB or more system memory you may be able to raise this limit substantially without performance problems, but do so carefully. You need to restart the session for the changes to take effect properly, and to test the new settings. If you set this value too high your textures may actually get worse and/or the sim may fail to load at all. (B) Check the current GPU load is near the specified GPU memory limit (within 100 MB or so) then it may be the setting that is limiting the texture quality too much. In this case you might try to raise it a bit and restart the session. Don’t raise this setting if it is not the limiting factor (as it will have no effect), and don’t raise it too far. Setting it too high may cause the simulation to fail to load, page faults, worse performance, etc. Generally we do not recommend setting it higher than the actual GPU memory capacity. A different, safer, option to improve texture quality when limited by video memory is to disable some other users of the video memory. For instance, turning off graphics options such as “depth of field” and/or “shadow volumes” (in BOTH replay and graphics settings) will free up a substantial amount of video memory, allowing better texture quality. Selecting “cache swap nearest cars” in the graphics options may help as well when limited by video memory. You need to restart the session for the changes to take effect properly, and to allow you to test the new settings. If you set this value too high your textures may actually get worse and/or the sim may fail to load at all. Q. I am now having new performance issues after the update? A. This may be due to the new GPU memory setting. Try lowering your max GPU memory slider from the actual amount of GPU memory to a lesser amount to see if it makes the issues go away. If this doesn’t help, put it back to the correct level and try lowering a different setting. Q. I am getting solid yellow or red bar in the new “P” meter”? A. Your system is using your disk drive to make up for lack of available physical RAM. The easiest solution is to lower the working set slider in the advanced graphics options to make the simulation use less RAM. If this doesn’t work you may benefit by adding RAM to your PC. Other processes and services running on your PC also use RAM, so it can help to reboot your PC and close down as many application as possible before running the simulation – to free up as much physical memory as possible. Q. I am getting intermittent flashes of green/yellow/red /gray bars on the new “P” meter, but it isn’t constant? A. This is normal, as long as they aren’t associated with huge stutters. Q. I am getting a solid gray bar in the new “P” meter? A. Your system is incurring a lot of interrupts to manage virtual memory. You may benefit from reducing your GPU memory slider and restarting the sim. If this doesn’t help try reducing your system working set memory slider. Soft page faults may not be that bad, but if you can get rid of them, it will surely help performance. Q. I want to raise my working set beyond 1536 MB but it won’t let me in the options screen? A. You may override the limit by setting it directly in renderer.ini. This is not advised. Q. I have 2048 MB of video memory but the load never exceeds 800 MB? A. Due to the possibility of needing to restore a lost Direct3D device (i.e., if you alt-tab in full-screen mode), the simulator keeps copies of textures, vertex buffers, and index buffers in system memory. The video driver also uses system memory in its operation. If the simulator’s predicted working set would exceed your specified maximum, the simulator is forced to reduce texture and geometry quality to keep the system memory working set in check. Raising your working set setting may allow your video memory load to increase (after a restart of the session), but doing so may also result in page faults and/or decreased performance for the CPU if set too high.