sorry to rant but ... All this still doesn't solve my Slow Burn Speed problem.. Great info though. Cheers, Mun Heng, Ow H/M Engineering Western Digital M'sia DID : 03-7870 5168 -----Original Message----- From: John Haxby [mailto:jch@xxxxxxxxxxxxxxx] Sent: Tuesday, September 30, 2003 12:58 AM To: shrike-list@xxxxxxxxxx Subject: Re: Burn Speed to CD-R (was Re: SATA problems) Brian T. Brunner wrote: >This will vary with disk models: > >Take the number of sectors, divide by the number of (cylinders * >heads), >this is the number of sectors that flies under one head in one >revolution of the disk. > >Factor in the spindle-speed of the disk, and you get the number of >sectors/second that pass under one head. > >Since only 1 head can be read or written at a time, this is the maximum >long-haul data transfer rate of the hard drive. > > Sigh. Would that it were that simple. The number of sectors per cylinder is not constant across the platter. Modern disks have a (nearly) constant size sector so you'll find that the outer cylinders transfer faster than the inner cylinders. If you can write a whole cylinder (that is, across several platters) you'll get better transfer rates that you will if you write on adjacent cylinders. In other words, a disk with a lot of platters will tend to be faster than a disk with a single platter. Current disk technology is somewhere around 45-50Mb/s (my shiny new disk is somewhere in this range). That's sustained data rate. This is rather faster that ATA33 (17Mb/s) and indeed faster than ATA66 (33Mb/s). Luckily I've got an ATA133 bus, but ATA100 would be fine (which is what this disk actually is). jch -- Shrike-list mailing list Shrike-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/shrike-list -- Shrike-list mailing list Shrike-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/shrike-list
