vinum vs. DPT smartcacheIV raid

[Willem Jan Withagen]

Peter C. Lai wrote:
> I have a box with DPT PM2044 SmartCacheIV UW-SCSI PCI cards which can do 
> RAID-5 in hardware, but I'd have to use the DOS volume manager to set up 
> the array. I have heard reports that vinum woudl be faster than using the 
> native card. Is this true? Should I not bother with doing the hardware raid 
> and just go with vinum?
> 
> The rest of the system is a k6-2 400mhz with 256mb ram (amount might change).
> I will also have moderate network i/o on the pci bus (obviously).

I still have one here lingering around somewhere on a shelf. It ran a 
4*1Gb diskarray RAID-5 when 1GB disk where still sort of big. So that is 
how old this card is.

With that I did have some unplesant experiences with this card:
- First and most major it seems that you need to have the right version 
firmware in it. Otherwise things might get seriously hossed at 
unexpected times. Just buffers timing out in the middle of the night.
- The other issue was that my disk where in an external cabinet and once 
the cable came loose. It killed the raid as expected, but it took me a 
long time to find some tools to force the disk up the brute way. Just to 
see if I could recover some of the data.
And like you say: Al these tools are DOS based.

Currently I'm running a 4*60Gb ATA RAID5 with old vinum on a 233 MHZ P2, 
256Mb with FBSD 5.1. This ATA just because ATA disk are so much cheaper 
per MB, and I do not need utmost dependability for my 6 PC office.
I've ordered 4*250Gb ATA disks this week to build a new RAID5, and I'll 
go again for vinum.

--WjW