Messages in this thread | | | Date | Tue, 8 Dec 1998 23:32:33 +1100 (EST) | From | Damien Miller <> | Subject | Re: Dumb question: Which is "better" SCSI or IDE disks? |
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On Tue, 8 Dec 1998, Leonard Zhang System Administrator ISD RVIB wrote:
> RAID-1 is disk mirror. DPT is cache with RAID. RAID will increase the > disk performance.
RAID-1 slightly *decreases* write performance, as writes will complete only after data is written to all disks in the mirror group. Writes therefore proceed at the speed of the *slowest* disk of the array. RAID-1 should increase read performance, however.
In any case I would hardly call a poorly conceived and statistically irrelevant 'benchmark' valid, especially when performed under SCO.
DPT controllers come with a lovely manual which explains in great detail SCSI, RAID, tagged queueing and all the other basic concepts that you have demonstrated an inability to comprehend. Please read it, as these are concepts that every self-proclaimed "System Administrator" should understand.
> On Mon, 7 Dec 1998, Alan Cox wrote: > > > > Open server 5.0.4p, DPT RAID-1, 32 MB cache, PCI, 4.2 GB (A cable) > > ^^^^^^^^^^^^^^^^^^^^^
You still haven't explained why you are trying to compare SCSI disk performance under SCO with that of IDE disks on Linux. (Free Clue - you can't).
Regards, Damien Miller
| Damien Miller - | Email: dmiller@ilogic.com.au (home) or damien@ibs.com.au (work) | WWW: http://www.ilogic.com.au/~dmiller/
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