Re: IDE Disk Problems

Floody (flood@evcom.net)
Wed, 12 Feb 1997 14:48:56 -0500 (EST)


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On Thu, 13 Feb 1997 bofh@snoopy.virtual.net.au wrote:

[snip]

> >Your next disk drives should be SCSI. You will probably never replace
> >them, only transfer them to other systems when you replace them with the
> >latest higher-speed, larger-space units when they become available.
> >One-point-two gigabyte drives are now considered "obsolete", you can get a
> >few for the cost of a real poor 2 gigabyte IDE drive. The only problem is
> >you will need a SCSI Controller and they are not cheap. A good one will
> >set you back maybe US$300.
>
> I have read a number of messages related to the quality of IDE drives and WD drives in particular and I believe that I have to respond to give the other side of the story.
> I have had what I consider to be a reasonable amount of sys-admin experience (including running an ISP for over a year). Currently I run 3 OS/2 servers, 5 Linux servers, 2 NT servers, and quite a few workstations. All the OS/2 and Linux machines have IDE hard drives, most of the hard drives are WD (about 10 WD drives in operation now, but I've gone got rid of a few of the smaller ones - 340meg drives aren't much use now). I have not had a single problem with a WD drive that could be attributed to the drive (mis-use of `rm` doesn't count as a drive problem). However with the NT systems running SCSI drives (Seagate and Maxtor drives mainly with Adaptec, NCR, and DPT controllers) I have had heaps of problems. Strange crashes on boot, data loss in running system, systems booting up and suddenly crashing when previously they had worked fine.
> Based on the experiences with SCSI the client has now decided to save money and buy IDE - the extra money they spent on SCSI wasn't getting them any extra performance or reliability.
>
> As for performance, I recall seeing a message from Mark Lord saying that in most Linux systems you won't gain anything from SCSI. Save the $300 on a SCSI controller and get 64meg of RAM - it'll make your system faster and more reliable than SCSI.
>
>
> Russell Coker

You can see an *immediate* performance difference if you compare two IDE
drives on a single IDE "channel" to two comperable drives on a SCSI bus.
It is most likely that the problems you experienced with SCSI and NT were
related to poor software design, rather than actual hardware problems. I
have experienced numerous problems myself with NT and hardware, problems
that mysteriously vanished once NT was replaced with a more stable OS.
This isn't to say that NT is unstable, given the right hardware, it just
seems to be exceedingly "picky" with much highend hardware.

Again, on the performance side, I get upwards of 25MB/s on either of my
Seagate UltraWide scsi devices; a measurement that you are very unlikely
to see on _any_ IDE drive (note: this is while the system is under
considerable load, too).

There can be no doubt that the combination of a well designed SCSI
interface and drive hardware with an OS which is capable of properly
handling the hardware will _vastly_ out-perform a similar setup using only
IDE technology.

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