A4000 and A4091

[mechy]

Hallo, I have a small issue with the scsi...

I have two fast disks, ibm DCAS34330 and Seagate Barracuda (all 4gb) but I not able to have speed over 5mb/sec. Sysinfo show me 4,5mb/sec, scsispeed 5mb/sec at max.

I have active termination, short cable, jumper is at synchronous and I have Buster 11.

My config is: A3640 v3.1, 16mb, kick 3.1, wb3.1, net a2065, merlin 4mb. No ide devices.

Maybe the merlin use to much zorroIII bandwith?

Another problem: at normal use I not have problems, but if I go in the boot menu and exit.... I have the kick screen! I need to manual reset to start hdd load. Same problem with wb3.9 kickstart replacement: it load the kick replacement and reboot to kick screen... I need to reset to loading the workbench. Why?

Do you have the latest rev 7.0 roms for the 4091?
Are you using active termination?


the ibm drive is a bit slow at only 5400 rpm,looking at the data sheet its rated 40Mbps external transfer rate,and guess what...this is about 5MB/s this drive is doing what it is supposed to.

The seagate barracuda(is this the one that sounds like a jet plane???) you dont give a model so i cant look it up, if its the 7200rpm version it should do a bit better i would think.

Things to check/try:

What filesystem are you using? FFS is slow, use SFS or PFS-AIO
Try the seagate alone if possible.
use active terminators.
try upgrading the roms if possible.

There could be contention with the merlin-those cards were known to be problematic,some even with the upgrades, you might take it out and try the tests.
Sometimes booting with a clean workbench 3x floppy and running the speed tests will give a clear true idea of speed.

Good luck and let us know what you find.

[mechy]

Thanks for the reply

Yes the barracuda is the jet! Is st15150n.

The A4091 is the DKB version, is the latest version? How I see the rom version?

File system is FFS, with FFS the speed does not go beyond 5mb/sec?

The barracuda is rated 10MB/s max burst speed, so i would think it could do more than 5MB/s.

look on the 4091 card , there should be a label on 2 chips stating what version roms. You can possibly version the scsi.device it uses in cli to find it.

FFS is known to be slow. sfs or pfs would prob. help.

are you using active termination and quality cables?

How do you stand the sound of that barracuda, its so loud and so hot,you could fry a egg on them ..lol

modern 10K rpm drives are likely quieter and run cooler than that thing

[mechy]

Ok, I ordered ad external active termination and the latest rom 40.13

But I have another question, I have checked the internal voltage of pin 26 (term power) and is ok 4,70v. But from external cable I have 0v.... I need to supply the terminator from external drive?

Is correct? The A4091 supply the internal power term but not external?

that is useable on the internal, but it appears you need to supply term power for external. Many drives can be set to do this. without power, termination will not work. Good luck.

[mechy]

The A4091 ROM won't replace anything in kickstart, rather it should should show up renamed as "2nd.scsi.device" (any IDE drives would continue to be managed by the scsi.device located in the Kickstart ROM).

Due to reliability issues with Z3 DMA, the transfer rate you're reporting is normal for the 4091. DMA to motherboard RAM (using a 3640 for example) is generally about 1 MB/s higher than DMA to accelerator RAM (and a bit faster still if the motherboard RAM is set to 60ns). Filesystem operations test roughly equivalent to accelerators I have here with onboard SCSI, so in practice, the 4091 "feels" very responsive using PFS3, and CPU use is negligible. (Sidenote: the Fastlane Z3 can be programmed to have a higher transfer rate than the 4091, but at the expense of CPU time). I use a 4091 with a CF AztecMonster in my 4000D, and really love the card.

Dave Haynie wrote lots of interesting info about the 4091 (various websites, and check the usenet archive).

What speeds are you seeing with 4091 and aztec monster?

[mechy]

Arrived active terminator and new eprom!

But if I run: "version scsi.device" have the same result... 40.12! Why?

you are doing version on the amiga 4000 scsi.device in 3.1 rom?

[mechy]

You may of seen this:
http://www.hough.ca/personal/4091.html#a3640
An interesting note here about how rev 3.1 A3640 needs u209 to be -03(aka like on rev3.2) or there are DMA problems supposedly.I never noticed this way back when i had a 4091.
not sure if this would impact speed.
At the end of the day a quality accelerator with scsi onboard is always best

[mechy]

I changed all capacitors on the A4091 but the problem is not solved...

I think you are getting all you can from that combo. If you want faster scsi i would suggest a good accelerator with scsi(not apollo).
Cyberstorm MK3/ppc will get you UWscsi at around 30-40MB/s.
warp engine, cyberstorm MKII,gvp4060DT,etc around 9-10MB/s