Zipped?

djaay · 27 Sept 2017, 11:31

Hi!

Some roms can be read while they are zipped. But does that means that RetroArch temporarly unzip a rom?

Does that mean that if you have zipped files....there will be more writings to your SD card? So it´s better to have them unzipped to minimize writings on your SD card?

I understand that if this happens...the temporary file will be removed once you are done playing the game. So this is not a "size of SD card" issue....it´s a "writings to SD card" issue.

mitu · 27 Sept 2017, 11:47

I don't think RetroArch unzips the archived roms on disk, it unpacks them in memory and then loads them into the emulator cores.

djaay · 27 Sept 2017, 12:00

@mitu Ah, didn´t think about that.

akafox · 27 Sept 2017, 16:21

ok so two questions:

Having them uncompressed makes them load faster yes? (at least a little)
if they are decompressed in ram does that mean I have less ram to use to run the rom?

I would save some space I'm sure if they were all zipped.

Oh I have another question..my pcengine/tg-16 roms are zipped because they have "sound" files to go with the roms themselves (I guess like a sound sample for mame?) but I wondered about leaving them uncompressed just to make it faster. I was also under the mis..interpretation that the rom was written to the sd card and writes were taking place...now that I think about it (after having my nose pointed n the right direction) it makes sense that it would use ram. But again leaving them zipped would save me same space! :D

djaay · 27 Sept 2017, 16:52

Unfortunally i found this bug that was reported 24 Dec 2015.

https://github.com/libretro/RetroArch/issues/2588

"Retroarch extracts them to the rom folder, and then does not always delete the extracted roms afterwards."

So it seems like RetroArch is extracting the zip files and putting the roms in a tmp dir before loading them. So from that post i do think it is best to have the roms unzipped...sure you lose some free space on the SD card. But i think it´s better then writing to the SD card.

mitu · 27 Sept 2017, 17:04

@djaay Like the issue says, you could configure it to unzip them in /tmpor in a memory backed folder. In Debian, /tmp is written in memory, so there is no writing to the disk.
As for the other aspect - RAM - I don't think it makes any difference: unzipping an archive to obtain the original ROM file would lead to the same memory used by the uncompressed ROM. The only - extra - memory would be taken by the internal unzipping routine, which should be easily reclaimed by the process once is finished.