SCSI Slow?

[logic28]

Hi guys, I have a question.

I am building a workstation with a combination of: PATA drives, SATA II drives, and SCSI Ultra-320.

Now, when I tested the Read / Write speed I obtained the following results in MB/sec:

PATA (IDE).................48.........43..........OK
SATA.........................62.........54........ ..OK
SCSI..........................28.........23....... ...VERY POOR

I thought there was something wrong with my onboard SCSI controller but when I tested the SCSI drives through an old 2940 Adaptec card (that provides at least 40 MB/s) I got exactly the same:

................................28.........23..... ...It must be the drives, I thought.

But even though they are not the latest, I never thought there was ever a SCSI so slow!
Or was there? :rolleyes:

Well, that is my question. I have never had reason to test drive speeds before so I am totally unaware of the performance of these drives nor I can find them on the net. I don’t want to blame the mobo yet, so I would appreciate any suggestions. ;)

SCSI DRIVES:

Seagate Cheetah....ST19101WC.............9 GB....Hot-swap
Compaq................BD018122C9...........18.2 GB....Hot-swap
Quantum............Atlas 10K 3.5 series...9.1 GB

Also, the two hot-swap drives don’t work at all unless an old 50-pin CD cutter is added at the end of the array.

I guessed that may be due to the 80 to 68-pin adapter possibly being too old and thus incompatible with U320. Possible?

And if so, why would they work in conjunction with the 50-pin SCSI device and not alone? :rolleyes:
I always added a terminator in all my tests.

I thank you all for your time.

Maz

[dinos22]

what hardware config exactly (mobo, drives, adapters.....) are you using and what OS

[nn_step]

The problem is with the Controller card not the Drives

[logic28]

It's a Tyan K8we s2895 onboard LSI Scsi contr latest drivers

Win XP SP2

[dinos22]

i used that motherboard before...i didn't have issues but i was told recently that WinXP has some issues with SCSI performance


It's a horrible stupid bug in Windows XP that plagued SCSI users for the last year or two.

In summary, it kills the performance completly. Microsoft released a solution at the end of last year however it there are limits.

Here is the Article/Faq (http://faq.storagereview.com/tiki-index.php?page=XpScsiProblems) at storage review about the bug and the fix

And ofcource the Microsoft Article (http://support.microsoft.com/default.aspx?scid=kb;en-us;332023) with the bug in Full detail

The sad thing is that you actually have to make an international Phone call to Microsoft support if you want the patch and the hotfix. Meaning ofcource that you must also own a legitimate copy of XP ;)

PM me if you need the files :thumb:

[logic28]

Thank you for the tip.

I'm looking into it.

Maz:)

[SlackerXL]

has anyone here got this patch or the other workarounds to work at all?
i 've had the same problem with my 2x73gb ATLAS 10kV & Perc3/dc controller
and i could not get the damn thing to work..
(nor the other patches...)

could it be a compatibility issue with my controller?

i would really like to keep my scsi drives
but for now, my raptors raid has better performance on a WinXP sp2 system
so i should either change OS or sell all the scsi stuff.. :(