Hacking Homebrew [Beta Release][Tester wanted] Kernel9 patch to speed up boot speed on high capacity SD card

[TheSunGodNika]

Unfortunately, GodMode9 doesn't calculate free space instantly.
GodMode9 doesn't calculate free space unless you "R+A (drive option)" -> "Show drive option" then you'll see "Analyzing drive, please wait..." (I guess it's calculating free space by reading through FAT) and you have to wait for a while depending on your SD card capacity.

Huh... interesting

Then how can OS' like Windows instantly calculate it??? More of a curiousity now that I see this reply

 

[Core_2_Extreme]

Huh... interesting

Then how can OS' like Windows instantly calculate it??? More of a curiousity now that I see this reply

I don't know for sure, but I think it's either

• It actually calculating free space as 3DS does but because modern HW can read data much faster (like 75MB/s+) we don't notice the delay.
• It uses FS information sector and trust it (if exists).
• It uses its own cache (maybe in registry or something idk) and show it as "free space" then calculate actual free space in background and update it.

 

[cylin577]

I can confirm that hshop, FBI, universal-updater work

 

[masterz81]

I can confirm that hshop, FBI, universal-updater work

So you can install games/apps normally without crashes or bugs?

 

[RAHelllord]

This is an interesting approach, though it is definitely heavy handed. Would it be possible to speed things up by storing the calculated space in a cache somewhere and just reading it from there during boot?

The cache could either be refreshed manually from the Luma3DS menu by the user, or automatically during shutdown. I'm assuming most people don't remove their SD cards every day so this option would keep it up to date well enough for most people.
And if its done during shut down (not reboot, full shut down) it also will likely not matter to people if the thing stays on for a 30s longer before the LEDs turn off, making it unobtrusive.

 

[angelus kun]

If someone is interested I tried to use checkpoint for backup and restore saves from installed games and works flawlessly and tried Pokémon Bank too and it works faster than before while access to SD and I tried the patch with 128GB FAT32 SD card and with patch it boots in 15 seconds, without patch boots in 20 seconds

 

[AlamosIT]

Amazing! Let's try!

 

[angelus kun]

I don't know for sure, but I think it's either

• It actually calculating free space as 3DS does but because modern HW can read data much faster (like 75MB/s+) we don't notice the delay.
• It uses FS information sector and trust it (if exists).
• It uses its own cache (maybe in registry or something idk) and show it as "free space" then calculate actual free space in background and update it.

After a day testing almost 10 hours playing I can feel a little heat form the bottom of my 3ds and then when I check temperature it raises from 35celcius without patch to 37 Celsius with patch idk why but definitely there is something with the patch

 

[a_username_that_is_cool]

I don't know for sure, but I think it's either

• It actually calculating free space as 3DS does but because modern HW can read data much faster (like 75MB/s+) we don't notice the delay.
• It uses FS information sector and trust it (if exists).
• It uses its own cache (maybe in registry or something idk) and show it as "free space" then calculate actual free space in background and update it.

It's using 2, that's how fake SDs and SSDs work, by just tweaking the "max space" on the FAT/firmware

 

[Core_2_Extreme]

The cache could either be refreshed manually from the Luma3DS menu by the user, or automatically during shutdown.

This is a great idea, however implementing it may not be easy because I don't think I can access kernel9 (or gm9) once it boots
Maybe I can implement something like "schedule cache refresh (calculate free space) on next boot".

Post automatically merged: Oct 23, 2025

After a day testing almost 10 hours playing I can feel a little heat form the bottom of my 3ds and then when I check temperature it raises from 35celcius without patch to 37 Celsius with patch idk why but definitely there is something with the patch

It shouldn't affect SD card temperature as it doesn't modify IO operation itself.

 

[autumns]

This is a great idea, however implementing it may not be easy because I don't think I can access kernel9 (or gm9) once it boots
Maybe I can implement something like "schedule cache refresh (calculate free space) on next boot".

Post automatically merged: Oct 23, 2025

It shouldn't affect SD card temperature as it doesn't modify IO operation itself.

ik the warning screen is just cause it’s pre-release but maybe in the final build you could add a toggle for the patch as an option in the luma config you get by holding select on boot. so it would boot fast normally but you could still toggle it before boot if you’d like.

if the patch can be disabled on the fly you could maybe add an option to rosalina menu to update the cache manually as well without having to reboot.

not sure if this would all work but seems like a clean way to handle it imo.

 

[Core_2_Extreme]

ik the warning screen is just cause it’s pre-release but maybe in the final build you could add a toggle for the patch as an option in the luma config you get by holding select on boot. so it would boot fast normally but you could still toggle it before boot if you’d like.

I can absolutely do this.

if the patch can be disabled on the fly you could maybe add an option to rosalina menu to update the cache manually as well without having to reboot.

I should be able to change the settings (the same settings you'll see when you holding select button on boot) via luma menu (the menu you can open anytime after booting), however to apply change I think we need to reboot the console.
So it will be something like [change settings via menu -> reboot now or later to apply].

 

[Blythe93]

Subscribed to the thread, looking forward to the future updates! That speed-up is insane.

 

[lightwo]

Is it possible to see remaining space in settings? The initial boost would absolutely be a major improvement (99% of the time, free space is not something I need to check), but I'd still like to be able to check free space without having to go to GM9.

Still, even in that case, I think it's fine enough. After all, the only way to know battery level is to open Rosalina (and yes, alternatives exist, but they break other homebrew), so this shouldn't be that big of a deal.

If this gets merged, it would finally mark the end of "just buy a 64 or 128 GB card" comments, since I'm sure there are people out there wanting to play their whole PS1 collection or something.

 

[Nyxicle]

128GB microSD card, New 3DS XL
Boot time went from 22 to 15 seconds. Incredible! Looking forward to the future of this, but I think I'll stick to stable Luma for now

 

[Riot20052]

Just test it

128gb microsd card

16 seconds boot up

512gb microsd card

10 seconds boot up
38 seconds load into GBA games [no changed just kinda needed some patience.]

Warming show way to much happen with you

Power on system
Chaged 3ds banks
Switch out of MicroSD Management
Leaved the settings apps

Could just have setting to accept the risk once and be done with it

Post automatically merged: Dec 13, 2025

Just test it

 

[Nyxicle]

Could just have setting to accept the risk once and be done with it

Post automatically merged: Dec 13, 2025

Just test it

honestly no, i agree with it staying accept every time. It's a serious risk you're taking with your data every time you boot up the console with this patch

 

[Riot20052]

honestly no, i agree with it staying accept every time. It's a serious risk you're taking with your data every time you boot up the console with this patch

Test it and work with everything every with microsd management mean did switch back to 128gb sd card just testing with 512gb one

Been report already that download things is fine.

Fact ask you this accept risk every single little thing on the system get really old very fast.

 

[Apache Thunder]

Test it and work with everything every with microsd management mean did switch back to 128gb sd card just testing with 512gb one

Been report already that download things is fine.

Fact ask you this accept risk every single little thing on the system get really old very fast.

Yeah that's the only thing I dislike about it so far. I understand why the warning needs to exist but I feel like it needs to be a one and done thing. It needs to save a setting so the nag doesn't happen on every boot because it does get old very fast.

 

[Riot20052]

Yeah that's the only thing I dislike about it so far. I understand why the warning needs to exist but I feel like it needs to be a one and done thing. It needs to save a setting so the nag doesn't happen on every boot because it does get old very fast.

Sees like patch is stable thier people have report able download things for Hshop and used Universal updater also test MicroSD Management and works fine no trouble every with this side of things

Only thing uneffective was GBA injector boot times reboot different mode make sense.

Killing thing all times ask for warming show up

1. Turn on the system
2. Switch 3ds banks not start up app afterpart of it for it.
3. Exit MicroSD Management
4. Exit settings app
5. Leaved GBA injection

Overall do think patch see work quite will at this stage and MicroSD Management is able tell correct how much space one has