Is hard disk necessary for not over-using the sd?

Question

I recently got my rPI and I was thinking about using it as a torrent hub: in case this word is not accurate, I mean that I want to run a torrent client on my box, freeing my other computers.

For that, would you advise to connect an external USB disk? Or having a very big SDcard (32+ GB) would be enough?

If i'm not mistaken I read somewhere that using only the SD would put too much stress onto it, and as it's not made for these kinds of usage, it would wear somewhat fast.

In general, in which other examples would you say that it's best to not use the SD card?

Thanks in advance!

Answer 1

In general about rewriting data on an SD card: It is true that writing constantly one the same space should wear it out faster, but SD cards have circuitry to prevent this, by actually keeping track of how often a place (sector) has been written. This means that SD cards wear out evenly.

If writing downloaded files can be considered rewriting data constantly, I guess so, but the frequency is not that high that is will make the life of the SD card much shorter, more on this can be found here

But maybe this is a more elegant option for what you want: only use a SD card for the OS and use (mount) a drive/directory over NFS to store the actual files that you receive from the torrent network. In that way you only use the cpu power of the RPi for the actual torrent activity and use the storage of a different system (over NFS) for the files.

Answer 2

I'm not sure about the actual wear & stress on SD card, but I can say that (based on my experience) just an SD card won't be enough for your torrenting needs. I'm using Transmission on my lightweight RasPi server with only 800kb/sec (8mbits~) network speed, still it gets often unresponsive, and while Transmission works CPU gets so overloaded with I/O wait's I simply cannot do anything on RasPi while it's working, even Transmission remote interface hangs.

To solve it, I tried two things:

• Limiting speed to something ridiculous. It was OK when I enforced 200kb/sec speed limit, got rid of most I/O wait calls, but it's not an acceptable performance.
• Simply inserted a USB stick (not even external disk) and configured Transmission to download there. It's now lightning fast and most of the time I don't even realize that it's running.

Summary: In theory, No. In practice, if you don't want a living hell kind of experience, yes. My SD-Card is Toshiba Class 10 16GB, your mileage may vary.