michael@stb.UUCP (Michael) (02/29/88)
I did some experimenting, and discovered that writting a file to a floppy takes about 7 minutes, verify off writting a file to a floppy takes about 15 minutes, verify on Writting a file to a floppy file system (m/n = 2/16) takes about 7 minutes, verify on, and 3.5 minutes with it off. Reading takes about 1.5 minutes from a file system, but about 7 minutes from the raw disk. The only difference between these is the interleave used. The raw disk uses diskutil's interleave (which you can't change), while the file system uses (essentially) every other sector, resulting in higher throughput (more time to work with the sectors before the next one comes by). Since this is such a significant difference (4.5 X for reads, 2X for writes), what can we do to change the formatting done by diskutil? This speedup would actually make floppy backups feasable. Michael -- : Michael Gersten <best> => uunet!ucla-an.ANES\ : ihnp4!hermix!ucla-an!remsit!stb!michael : sdcsvax!crash!gryphon!denwa!stb!michael : "A hacker lives forever, but not so his free time"