Noticeable Lag While Saving

[JMC47]

It appears that melonDS does not asynchronously write savefiles, as whenever games like Mario Kart DS save a ghost file, my framerate drops tremendously. The issue disappears if I move the game/save to a solidstate harddrive.

Other emulators have asynchronous flushing to file to prevent issues like this.

[Arisotura]

good point

[nathanielcwm]

It's noticeable in Ace Attorney as well

[Zettymaster]

Noticable in Pokémon Platinum as well, very pronounced sound lag, FPS drop from 60 to ~45. i am on a SSD

[RSDuck]

for some games like 4th gen Pokemon games you have to keep in mind that it taxes the CPU more than usually during saving, because it does encryption and what not on the save file. For some reason that's not the case for 5th gen Pokemon games, I guess they've optimised it at that point (it's also far quicker).

[Liger0]

It also slows down on 5th gen, although less.

[ichee]

62e3f41 seems to fix this issue, though I don't have all reported games to test with.

Castlevania Dawn of Sorrow was affected as well, but not after this commit.

[RSDuck]

https://github.com/Arisotura/melonDS/commit/62e3f41f20866388287329218810d2fd8cea3515 still didn't really fix it (as the IO operations are still completely synchronous), though I'm happy to hear that this change atleast alleviated the problem.

[RSDuck]

fixed with https://github.com/Arisotura/melonDS/pull/925