Emulator Issues #9360
Disc load speeds no longer accurate after 4.0-8919
Tested: Rayman 3 and Rayman Arena, may effect other games
Game ID? (right click the game in the game list, properties, info tab)
GRHE41 for Rayman 3, GRYE41 for Rayman Arena
MD5 Hash? (right click the game in the game list, properties, info tab, MD5 Hash: Compute)
40386ae7cb46600bf05e8980c0773ffc for Rayman 3
4e7b4dd0444ebfeb7ec2ab253116d437 for Rayman Arena
What's the problem? Describe what went wrong.
Any builds after and including 4.0-8919 no longer emulate disc load times accurately, at least on the two games I have tested. In both cases after build 4.0-8919 the load times decreased by around 2 seconds, equivalent to if "Speed up Disc Transfer Rate" were checked. I have verified using recordings from a Wii (albeit not my own, but from someone I trust) that the previous, longer load times were accurate.
What steps will reproduce the problem?
Time a loading screen on either Rayman 3 or Rayman Arena (other games may be affected, I do not currently have the resources to test that) on both 4.0-8919 and 4.0-8916. On build 4.0-8916, the load times should be around 2 seconds longer.
Which versions of Dolphin did you test on? Does using an older version of Dolphin solve your issue? If yes, which versions of Dolphin used to work?
4.0-8919 - FAILURE
<=4.0-8916 - SUCCESS
What are your PC specifications?
Intel 4690, Nvidia GTX 970, Windows 10 x64, Samsung 850 Evo (on which the game is stored)
#2 Updated by JosJuice over 3 years ago
That 4.0-8919 makes loading times faster sounds normal, but I would not have expected that it makes loading times drift away from console timing so much that they match Speed Up Disk Transfer Rate. The bug that 4.0-8919 fixed was most likely hiding timing flaws we have elsewhere in the code, so I'm not sure what can be done about this... It's not impossible that the change created a new timing flaw, though. It would be good if others can contribute with loading time measurements from other games.
#3 Updated by RibShark over 3 years ago
That 4.0-8919 makes loading times faster sounds normal, but I would not have expected that it makes loading times drift away from console timing so much that they match Speed Up Disk Transfer Rate.
On further testing, it seems like I made a mistake when timing it, and you are correct that while it makes load times faster, they do not drift that far. I'm sorry if I caused any confusion.
#4 Updated by JosJuice over 3 years ago
- Status changed from New to Invalid
No, thank you for making the issue report and then correcting it when needed. It wasn't an inconvenience, and if you hadn't made this, I wouldn't have realized that the loading times became slightly faster. I am however going to mark it as invalid, because we're still in the same situation as before 4.0-8919: Dolphin's loading times are slightly too fast because we don't have a correct model for how the read head moves when seeking.
#6 Updated by RibShark over 3 years ago
Actually, it seems like that change uncovered a timing bug, not just something that's a bit inaccurate. It should be fixed by this PR, but I haven't tested it: https://github.com/dolphin-emu/dolphin/pull/3673
I just tested the PR, and it seems load times are back to what they were before 4.0-8919.
#14 Updated by JosJuice over 3 years ago
- Status changed from Fix pending to Fixed