On Wed, 2005-09-28 at 12:03 -0400, Ron Peacetree wrote: > >From: "Jeffrey W. Baker" <[EMAIL PROTECTED]> > >Perhaps I believe this because you can now buy as much sequential I/O > >as you want. Random I/O is the only real savings. > > > 1= No, you can not "buy as much sequential IO as you want". Even if > with an infinite budget, there are physical and engineering limits. Long > before you reach those limits, you will pay exponentially increasing costs > for linearly increasing performance gains. So even if you _can_ buy a > certain level of sequential IO, it may not be the most efficient way to > spend money.
This is just false. You can buy sequential I/O for linear money up to and beyond your platform's main memory bandwidth. Even 1GB/sec will severely tax memory bandwidth of mainstream platforms, and you can achieve this rate for a modest cost. I have one array that can supply this rate and it has only 15 disks. It would fit on my desk. I think your dire talk about the limits of science and engineering may be a tad overblown. ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
