On 2010-05-30, Neil Bothwick <n...@digimed.co.uk> wrote: > On Sat, 29 May 2010 07:59:31 -0400, David Relson wrote: > >> Indeed flash drives _do_ have a lifetime. My recollection is that it's >> in the thousands of writes if not the hundreds of thousands of writes. >> Assuming a life of 1,000 writes and you backup once daily, that's 3 >> years of backups. 10,000 writes would be 30 years. Of course if you >> backup every hour, 10,000 writes is a year (or so). > > You're assuming that each backup only writes once, which is far from > true. If you mount a drive with the sync option, the FAT is updated for > every block you write, so even a single file can cause thousands of > writes to the same location.
And you're assuming that the flash controller chip in the USB drive doesn't do wear-leavelling. -- Grant
