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ROMS off USB instead of SD

Posted: Sun Jul 31, 2016 10:10 pm
by RetroGamingNow
I had a thought about using a micro sub drive to run the roms off of. My question is do they run better or faster when kept on the sd card or would that not make a difference. Was thinking about using something like this https://www.sandisk.com/home/usb-flash/ultra-fit-usb so my son could have it without damaging or loosing the SD card. I could keep it inside the actual pi and have this on the outside of where the port is. Any thoughts?

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 10:40 am
by RetroGamingNow
Anybody? Lol

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 11:03 am
by Ganreizu
I don't think you can run roms off a USB stick. You can only transfer them to the micro SD from there.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 11:09 am
by Raft
According to this you can do it. Also I wonder if it's possible by just creating a symbol link. Like ln -s /dev/sdb/roms /home/pi/RetroPie/roms.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 1:56 pm
by RetroGamingNow
Raft wrote:According to this you can do it. Also I wonder if it's possible by just creating a symbol link. Like ln -s /dev/sdb/roms /home/pi/RetroPie/roms.
No idea what a symbol link is. lol

I have been running roms off of a USB with the pi3 since i bought it. Works pretty well but wondered if it ran better off of the sd? I thought more people would have some insight to this actually.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 2:00 pm
by Ganreizu
RetroGamingNow wrote:No idea what a symbol link is. lol
https://en.wikipedia.org/wiki/Symbolic_link

It's basically a reference to a file by using it's file path. Ex. Operating system tries to find a file in the SD card, finds a symbolic link that leads it to a file path on the USB stick instead and launches it that way.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 2:09 pm
by RetroGamingNow
Ganreizu wrote:
RetroGamingNow wrote:No idea what a symbol link is. lol
https://en.wikipedia.org/wiki/Symbolic_link

It's basically a reference to a file by using it's file path. Ex. Operating system tries to find a file in the SD card, finds a symbolic link that leads it to a file path on the USB stick instead and launches it that way.
I see - that makes sense. Like i said, i have been running the roms usb on my pi 3 since i started messing around with these things. I find it easier than tryting to move the roms to the sd card. But if the performance of the rom is compromised by this then its definitely not worth it to go that route. Hopefully someone knows if there is a difference in runnig from the two different drives.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 2:13 pm
by Ganreizu
RetroGamingNow wrote:I see - that makes sense. Like i said, i have been running the roms usb on my pi 3 since i started messing around with these things. I find it easier than tryting to move the roms to the sd card. But if the performance of the rom is compromised by this then its definitely not worth it to go that route. Hopefully someone knows if there is a difference in runnig from the two different drives.
I would think that if the transfer rate of the USB was higher than the micro SD it would be faster to run off USB, but i think USB read/write speeds are lower than micro SD cards generally? Not sure on that.

Re: ROMS off USB instead of SD

Posted: Mon Aug 01, 2016 2:29 pm
by RetroGamingNow
I would think that if the transfer rate of the USB was higher than the micro SD it would be faster to run off USB, but i think USB read/write speeds are lower than micro SD cards generally? Not sure on that.[/quote]

Googled and found this:

The now-aging USB 2.0 standard can theoretically transfer data at a very high 480 megabits per second (mbps), or 60 megabytes per second (MBps).

That's impressive, but not as much as the newer USB 3.0, which can handle up to 5gbps (640MBps)—over ten times as fast as the 2.0 maximum.Jun 26, 2014
USB 3.0 speed: real and imagined | PCWorld
http://www.pcworld.com/article/2360306/ ... gined.html

I have been using this SD card : https://www.amazon.com/Samsung-Class-Ad ... B00IVPU7KE

Read write speed of 48mbps


Would seem to me it may run quicker off of the USB

Re: ROMS off USB instead of SD

Posted: Tue Aug 02, 2016 1:26 am
by Raft
I'm not sure about speed of USB2.0 and SD card, I think they are pretty the same, but I think keep system and roms in separated drives can extend life of your system's SD card. Not sure about, but I think count of read/write operations for SD without roms will be less.