To: FuzzFace who wrote (40922 ) 12/19/1997 5:52:00 PM From: AreWeThereYet Read Replies (1) | Respond to of 58324
Edwin, I said CPU utilization will be comparable to SCSI (less than 10%) if it is using bus master driver. And even if it is not used, it won't affect not the sDTR. You just have less CPU time for other process. Bus mastering is different than DMA mode 2. I am using a PIO mode 4 HDD with 82371 Bus master HDD controller (all Intel 430/440 chipset will do)! The # reported by Winstone, Winbench... are all real life benchmark which estimate the effective DTR you will get. If you subtract OS overhead and access time, latency, you can actually obtain the sDTR of the spec. Also please know that HDD's sDTR is not constant, it is faster from outer track and slowest in inner track. If WinBench report avg 5MB/sec then the HDD probably can do max 7-9MB/sec. To test the real throughput of a HDD, there is a very good benchmark utility called CheckHD. It will calculate the real horsepower of a HDD for you. The internal DTR given by the spec is usually calc from spt, rpm base on a standard formula. There is no cheating involved. Also, it is funny you mention RAID 0. Unless my memory is wrong, RAID 0 is refer to disk-mirroring (or is it RAID 1???) or the lowest level of disk array setup. Disk mirror will have no performance benefit but 16MB cache will increase real life performance somehow but not sDTR. Smart people won't trust just one "actual testing". During my research on PP SparQ, I heard some non-sense figure like 1.5MB/s (you may able to locate the post from dejanews) but this is just another invalid "actual testing". :o) Will I simply use that post as a reference to say that PP SparQ DTR is 1.5MB/s??? aC