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?
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?
I always added a terminator in all my tests.

I thank you all for your time.

Maz

 

[unhappy_mage]

I don't know why they would only work part of the time. However, I wouldn't expect too much out of those disks - they're how many years old, now? 30 MB/s is pretty good for disks of that era.

 

[PaHick]

I didnt look at the others, but I did the Seagate Cheetah....ST19101WC. Their site specs list ....

UNFORMATTED CAPACITY (GB) ________________11.7
FORMATTED CAPACITY (GB) __________________9.1
AVERAGE SECTORS PER TRACK ________________170 rounded down
ACTUATOR TYPE ____________________________ROTARY VOICE COIL
TRACKS ___________________________________104,416
CYLINDERS ________________________________6,526 user
HEADS ______PHYSICAL______________________16
DISCS (3.5 in) ___________________________8
MEDIA TYPE _______________________________THIN FILM/MR
RECORDING METHOD _________________________PRML (0,4,4) ZBR
INTERNAL TRANSFER RATE (mbits/sec)________122 to 177
INTERNAL FORMATTED TRANSFER RATE (MB/sec)_11.3 to 16.8
EXTERNAL TRANSFER RATE (mbyte/sec) _______40 Sync
SPINDLE SPEED (RPM) ______________________10,033
AVERAGE LATENCY (mSEC) ___________________2.99
BUFFER (/optional)________________________512/2048 KByte
Read Look-Ahead, Adaptive,
Multi-Segmented Cache
INTERFACE ________________________________Ultra-SCSI Wide
ASA II, S.M.A.R.T., SCAM level 1 (2 optional)
BYTES PER TRACK __________________________
SECTORS PER DRIVE ________________________
TPI (TRACKS PER INCH) ____________________6932
BPI (KBITS PER INCH) _____________________94 to 135.4
AVERAGE ACCESS (ms) (read/write)__________8.2/9.7
Drive level with controller overhead
SINGLE TRACK SEEK (ms) ___________________0.8/1.2
MAX FULL SEEK (ms) _______________________19.2/20.2
MTBF (power-on hours) ____________________1,000,000
SHOCK (G's, 11/2 ms):
operating (Read/Write) __________2
abnormal ________________________10
nonoperating ____________________50/140
ACOUSTICS (Bels typical, sound power) ____4.6
POWER DISSIPATION (watts/BTUs) Active ____22.2/76
Idle ______20/68.4
POWER REQUIREMENTS: +12V START-UP (amps) _3.22
+12V TYPICAL (amps) __1.34 idle
+5V START-UP (amps) __0.93
+5V TYPICAL (amps) ___0.80 idle
IDLE (watts) _________20.7
LANDING ZONE (cyl) _______________________AUTO PARK
IBM AT DRIVE TYPE ________________________0 or NONE

Physical:
Height (inches/mm): 1.63/41.4
Width (inches/mm): 4.00/101.6
Depth (inches/mm): 5.75/146.1
Weight (lbs/kg): 2.3/1.04

That..INTERNAL FORMATTED TRANSFER RATE (MB/sec)_11.3 to 16.8...sums that part up right there. Not sure about the rest.

 

[dirtydr]

I was going to ask what your sync rate was because that is around UW (40MB/s) speeds. I dont believe anyone made a 9GB U320 drive(?). As to the 80>68 pin adapters, some of them do not support lvd which would force the drive to sync at 40MB.

Edit: It appears your Compaq is U2W, the Quantum is U160 and as pahick posted the Cheetah is UW. If you have them all on the same cable this is going to hurt the performance of the 'faster' drives. If you have not tried this already, plug in the Quantum by itself and try the test again. Your sync rate in the controller bios should be 160. If it is not either the cable is bad or the adapter does not support LVD. And whadda ya mean slow?! Those drives screamed ..... 5 or 6 years ago

 

[logic28]

I tested the drives in stand alone( whit the exeption of the two that would not work without the Plextor PX-R412CI CD writer at the end of the cable;
connected to the 68 cable via a 50-68 adapter which I understand includes a 50-line terminator.
The moment that drive is unplugged from the cable the other two drives disappear from the LUN scan.


I will aquire some proper scsi drives no question if I know the Lsi controller can handle a decent d.rate. This guy worried me a lot!!

http://www.hardforum.com/showthread.php?t=1029066


The motherboard is a Tyan K8WE S2895 with an LSI SCSI controller.

The lowest rate was registered on the Cheetah ST19101WC and it was below 20 MB/s.

The highest, 28 / 23 was from the Compaq BD018122C9.

The Quantum Atlas 10K 3.5 series only provided 23 / 17 MB/s.

All these tests were carried out on an off-the net benchmark but my safest test is to capture uncompressed video.

That is 19.7 MB/s for video plus 6 MB of audio which is a total of about 26 MB/s.

None of the Scsi would capture for more than 30 sec. and then give up:

All the others,(Hitachi desktstar..(62-52); WD 1600JD Caviar..(48 40) captured over 3hrs of uncompressed video, even a Maxtor diamondmax 10 160 Ide made it.

The 80 to 68 adaptors don't carry a brand but just a "MC 80" and they were bought in the UK in 1999.

the cable is the new Scsi U320 that came with the Tyan.

 

[defakto]

If the drives disappear when the cd drive is unplugged it's because you don't have proper termination. Which is what the cd drive was giving you.

 

[logic28]

i did have the active terminator at the end of the cable tough.

I wonder if there was a mismach between tehrminator and 80 to 64pin adaptor.

I looked for instructions on how to use theese adaptors but could not find any on the web.

There are several jumpers like MTP, DLY, SIN,

They always worked in the past for me maby due to the Cd attached.

 

[draksia]

For more capable drive I recomend the Maxtor Atlas 15kII it is the fast hard drive you can buy. If you need more space both Maxtor 10KV and Fujitsu MAT series are excellent.

I personally have Atlas 10kV and have been very pleased with it.

 

[DougLite]

Fujitsu MAU for desktop application performance. Atlas 15K II for server and synthetic performance.

My Atlas 15K II is great. I got it for $90

 

[dirtydr]

Do your adapters look like this on the 80 pin side? (sorry for the uber-crappy pic)

If so they do not support LVD and you will need to get new ones to run 80 pin drives faster than 40MBs.

 

[logic28]

It seems slightly different, it does not have the loop track that I can see in yours.

Still, even if it is an UW the drives are not getting anywhere near the 40GB mark.

I'm trying to send you a photo but, how do you do it?

 

[dirtydr]

Try using a free image uploader like photobucket. I have been through the adapter problem a number of years ago. Having purchased some 80 pin U2W drives I set out to get adapters knowing that there are specific ones needed. The first few sets that arrived were as shown in my picture and would not sync above UW. Every time I actually called the vendor and asked "Do they support LVD" and the reply was "Yes, they do... so what was that credit card #". Bastards .

Anyway the last non functional set I received actually did have connections from the 80 pin connector to solder points but would still not sync at the drives speed (80MBs) so the lack of that loop is not the be all end all determination as to whether they are the 'right' ones, but if they did have that, you'd surely have the wrong ones.

Since that is not the case, just for the hell of it maybe try hooking up the U160 by itself on the 1st connector (closest to the controller) on the cable and do not terminate the chain. See if the drive will sync at 160 in the controller bios. This is not recommended for anything other than testing but it should work.