Could you please only quote the relevant parts, particularly, would you erase deeper nesting of quotes in your replies? That'd help a lot of people transfer less data they can still easily get from their own mailer at a keypress. Thanks a lot.
On Tue, 25 Sep 2001, Jorge Ner�n wrote: > Who says test.zero is a linear file and it's not scattered around the > whole disk and the fs layer is filling holes...? If it's the case the > write cache is a BIG win, just think that the fs writes a chunk at the > beggining of the disk, then another chunk at the end, then another near > the beginning, then... you get the picture, in this case the disk > reorders the seeks to best fit. > > If you want to try a REAL linear write do a dd if=/dev/zero of=/dev/hde7 > or whatever unused partition you have. I did, and it showed almost the same behaviour, twice as fast with write cache turned on. Scattering the writes would (usually) only happen on a nearly filled disk.
