Re: Linux on AMD K6

linux kernel account (
Thu, 10 Jul 1997 18:21:16 -0400 (EDT)

On Thu, 10 Jul 1997, Christoph Lameter wrote:

> In article <> you wrote:
> : Vadim E. Kogan <> wrote:
> : > 2. SCSI doesn't make big difference if you have enougth RAM
> : The impact of IDE on a web server with enough RAM isn't latency
> : or transfer rate -- it's cpu lossage. With a typical IDE setup,
> : you can drop packets from this.
> And that only happens if you have not configured the harddrive to either
> A. Use DMA
> B. allow interrupts during transfer (hdparm command)
> IDE is faster and more stable than SCSI especially with modern motherboards.

So.. You are telling me that, if I pick a IDE drive at random which
supports PIO4/DMA (say a WD) and put on a good motherboard. Then I have 50
people logon and do their verious things, compiling ETC. You would have
be believe that if I compaired this to a setup with a BT-948 or a DPT raid
and a fast baracuda the ide would be 'MORE STABLE' and 'FASTER'?? Somehow
I seriously doubt it...

Try not to use absolutes, it indicates ignorance. Yes, in certian places
IDE can be better.. But if you enable DMA on many current IDE drives you
will risk corruption.. Of course IDE will outperform a 1540.. But
compaired to a 2940/a BT-948/or a PM3334UW.... I really dont think so..

The current problems with scsi stability are because of the drivers.
There are many more people out there using the relitivly cheap IDE stuff..
And few using the SCSI stuff.. Also, if you get IDE right on the 430Hx
chipset then you've gotten it right for most of the IDE market.. If you
make the 2940 driver perfect, how many peoples problems have you solved?
Since there are relitivly few IDE combinations, and relitivly many IDE
users it isn't hard to make good solid drivers for them...

Also, try making a 7disk RAID-0, on a single IDE bus.. Or try finding a
single IDE drive over 20gigs... There are some things each technoligy is
better suited for.. IDE is wonderful in single user systems, which are
made to be as inexpensive as possible.. SCSI is GREAT in multiuser servers
and such where price is less of an issue and performance and expandibility
are king.

Everyone should pick the right equipment for their job. SCSI is more
expensive.. So it's not for everyone... but, what ide drives can measure
the fly height of it's heads and report impending failure to the
controler.. :)