.cso vs .iso

[EvilKingStan]

I have a pretty small sd card, so I'm thinking of compressing all my psp iso's to cso's. I know that they're smaller in size, and because of compression would take longer to load, but would it have any affect on gameplay speed?

[[Unknown]]

Gameplay speed, no (unless the game is written poorly.)

Loading speed, maybe a bit, but should not be much. What will matter more is the quality of your SD card anyway.

If you have a class 2 (slow) SD card, using a cso might very well improve loading speed, because it will be reading less data (and at 2 MB/s that's probably a bigger deal than the little CPU power decompression uses.)

Even if you have a class 10 (fast) SD card, cso might still speed it up, and if it doesn't, it probably won't affect it much.

This might possibly change if some kind of threaded IO is implemented. At that point, loading animations might potentially suffer from cso if they are very cpu intensive (but even then, probably not much.)

-[Unknown]

[EvilKingStan]

Great! Thanks for the info. I've been testing the compressed games since posting this thread and everything is exactly as you said. Thanks for the help.

[hacker3220]

(01-30-2013 01:28 AM)[Unknown] Wrote:  Gameplay speed, no (unless the game is written poorly.)

Loading speed, maybe a bit, but should not be much. What will matter more is the quality of your SD card anyway.

If you have a class 2 (slow) SD card, using a cso might very well improve loading speed, because it will be reading less data (and at 2 MB/s that's probably a bigger deal than the little CPU power decompression uses.)

Even if you have a class 10 (fast) SD card, cso might still speed it up, and if it doesn't, it probably won't affect it much.

This might possibly change if some kind of threaded IO is implemented. At that point, loading animations might potentially suffer from cso if they are very cpu intensive (but even then, probably not much.)

-[Unknown]

I don't think so... I've tested iso and cso of "the third bithday" and the iso file is a bit faster

[Henrik]

Got measurements of that? Otherwise it might have been slowed down one time by some background apps or something. I do think that in most cases you won't be able to see a noticeable speed difference between CSO and ISO.

[Carter07]

I think it depends from the game, for example gta streams data constantly and in the original psp was very laggy if compressed with cso.

But the overhead probably was, in proportion, higher in the original psp compared to 1ghz+ phones so now the difference in performance can be negligible.