archiving data, was RE: Media Longitevity/Care

On Sun, 20 Mar 2005 09:47:36 +0000, jpero at sympatico.ca <jpero at sympatico.ca> wrote: Flash isn't a perfect replacement for rotating magnetic media for any OS that has a swap partition... heavy use will begin to deplete regions of the Flash media. Before anyone says that it will take "X million years..." I want to comment that I've seen it happen myself in heavy use situations... specifically, I rigged up an old Olympus camera as a webcam for my "EarthDial". I used this camera because it was the end of summer at the South Pole and there wasn't time to get get something more suitable before our 8 month winter started. The camera was controllable via RS-232 serial line and gphoto. The one weakness was its 8MB SmartMedia storage. I took several thousand pictures, one every 5 minutes for several weeks. As the weeks wore on, the capacity of the card diminished by about 5%. Also... I happen to have a small stack of 4MB CF cards. I've never seen any with lower capacity than that (in full-sized PCMCIA form-factor, I happen to have 2.5MB cards, and ISTR there were 1MB cards). The low end doesn't matter for a theoretical RL02 replacement... those are 10MB. In the case of the DF32, we've looked at battery-backed SRAM, not CF. The one end-to-end (not platter-only) replacement project uses a 40-pin potted SRAM/battery combo like the clock/SRAMs in a SPARCstation, but much larger. With RAM sizes, etc, it's not absurd to consider SRAM for an RK05 or RL01, but by the time you get to RL02 sizes, board size and component expenses start to climb. Nice description of modern platters... I knew some of that stuff, but not the details. Certainly relevant to the issue of someday folks like us having to manufacture replacements. Unfortunately, not as relevant to the more immediate requirement to make or re-make DF32 platters, which are not like aluminum/glass platters. -ethan