Plugged into the computer that is, with its little light on, even if you do not actually read from it or write to it very much. Will it fail more quickly if kept plugged in as opposed to being plugged and unplugged every time you want to use it?
There shouldn’t be any problem with leaving it plugged in all the time. The only place there might be trouble is if it gets very hot.
I’ve had problems on linux boxes if the computer fails for some reason (e.g. power outage) and the drive doesn’t get shut down properly. Everything on the drive was lost, but the flash drive wasn’t permanently damaged, just required a reformat.
Haven’t had that type of problem on a windows box.
The only thing that makes flash drives wear out faster is writing to them. If you aren’t writing to it then you aren’t making it wear out. (ETA: except heat, as already mentioned, which generally makes all electronic devices wear out faster)
Some flash devices - especially with cheaper underlying processes, could actually be susceptible to something called a read disturb. I’ve had to add code to drivers to check for it for certain cases. But it’s unlikely that you’ll actually experience anything like that.
Wearing out due to write cycles is much more likely. Happily, that’s still pretty unlikely to happen to the average user.
-D/a
Hmm, how hot is likely to be a problem? It does get fairly warm when plugged in, even when not written to or read from. It has a bare metal housing, so I can feel it. It did once have a plastic insulating cover, but that got lost, which is partly why I dont want to carry this particular drive around in my pocket any more like I used to, but just leave it plugged-in instead. I guess the lost cover means it can dissipate heat more easily than it would otherwise, but it still gets warm just plugged into a USB hub for a while. I expect my CPU gets a lot hotter, though.
It certainly shouldn’t be running so hot that the ratings of the electronics are exceeded, but otherwise it shouldn’t be much of a concern, even when you consider than the data retention time is much shorter at elevated temperatures, because manufactures guarantee a data retention time of (usually) 10 years at the maximum rated operating temperature for Flash memory; at lower temperatures, that turns into centuries or even millennia, as demonstrated in this paper (PDF), which also shows how they can back up their claims without actually testing them for 10 years:
(150°C is VERY hot; maximum temperature ratings are typically 85°C, which is still far too hot to touch, 55°C might be found in hot electronics but still seems excessive for a Flash drive)
The one I have (which is 7 years old and has no problems, the first and so far only USB drive I own) does get warm as well, but nothing that concerns me (although I only plug it in when I use it). The only other thing I can think of is on the lines of what D/A said, which could happen if you turn the computer off while it is plugged in, but not always every time; sometimes they will be fine for a while and then lose data.
Cost of being fast: Every time a write actually goes out to disk (even a solid-state ‘disk’), things get a lot slower. Caching in RAM until a more opportune moment makes everything feel snappier.
That, and the fact FAT was a horrible file system 30 years ago and hasn’t improved with age.
Also, it’s possible to make things more reliable than fast if you read ‘man mount’ for comprehension, particularly about ‘-o sync’.
If you use it as a ReadyBoost drive in Windows (meaning: you tell the OS it can use the flash drive as a fast memory cache during boot), the drive will have a LOT of data going in and out of it every time you boot.
Whether that’s a problem or not depends on:
- The quality/age of your USB drive (obviously more expensive and newer = better)
- How often you reboot
I wouldn’t worry about it personally. Plus if a ReadyBoost drive fails, you just need to do a full boot next time and there’s no real harm done.
In my experience, the biggest danger is that someone will bump against the computer, or you’ll drop your laptop, and the USB flash drive will break at the connector, or damage the USB port on your laptop.