>Can you boot from that disk?

Yes,

>>>show dev
dkb0.0.1.4.0               DKB0                    ST316002 1A  3.06
dkc0.0.0.1010.0            DKC0                       RZ2CC-KB  DC2B
dkc100.1.0.1010.0          DKC100           SEAGATE ST318436LW  0005
dkc200.2.0.1010.0          DKC200            SEAGATE ST318417N  0105
dkc500.5.0.1010.0          DKC500     PLEXTOR CD-R   PX-W1210S  1.06
dva0.0.0.0.1               DVA0                              
ewa0.0.0.3.0               EWA0              00-00-F8-75-5E-6F
pkc0.7.0.1010.0            PKC0                  SCSI Bus ID 7  5.57
pqa0.0.0.4.0               PQA0                       PCI EIDE
pqb0.0.1.4.0               PQB0                       PCI EIDE
>>>

"boot dkb0" worked fine.

>Bechmarks? (bonnie?)
>What CPU load do you get on heavy IDE activity compared to SCSI?

I only had access to the disk for one night and didn't run a real 
benchmark using it.  The best I can offer is the time it took to copy 
files to it from two different partitions on SCSI disks.  The first 
source partition I used was on a ccd volume spread across dkc100 and 
dkc200 (I thought I'd make a 50 GB file for fun).  The SCSI 
controller was a QLogic ISP1040B.

isp0 at pci1 dev 10 function 0: QLogic 1020 Ultra Wide SCSI HBA
isp0: interrupting at dec 550 irq 20
scsibus0 at isp0: 16 targets, 8 luns per target

pws500# ls -l
total 6817458
-rw-r--r--  1 root  wheel  1073741824 Mar 28 17:06 1-GB-file
-rw-r--r--  1 ray   wheel  5368709120 Mar 26 02:29 5-GB-file
-rw-r--r--  1 root  wheel   536870912 Jun  2 20:53 512-MB-file
-rw-r--r--  1 ray   wheel         335 Mar 29 10:43 p.c
pws500# /usr/bin/time cp 5-* /mnt/big*
       384.77 real         0.19 user       137.30 sys
pws500# /usr/bin/time cat 5-*>>/mnt/big*/*
       383.37 real         0.75 user       155.97 sys
pws500# sh
# ls -l /mnt/big*
total 10490888
-rw-r--r--  1 root  wheel  10737418240 Jun  3 01:05 5-GB-file
# for i in 3 4 5 6 7 8 9 10
>  do
>  /usr/bin/time cat 5-*>>/mnt/big-file/5-GB-file
>  done
       385.17 real         0.62 user       156.62 sys
       385.79 real         0.76 user       154.76 sys
       387.61 real         0.81 user       159.38 sys
       385.15 real         0.65 user       159.89 sys
       388.79 real         0.76 user       155.33 sys
       393.55 real         0.69 user       160.51 sys
       400.23 real         0.76 user       160.21 sys
       397.02 real         0.77 user       155.28 sys
# ls -l /mnt/big*
total 52454424
-rw-r--r--  1 root  wheel  53687091200 Jun  3 02:12 5-GB-file
# wc -l /mnt/big*/*
  838860800 /mnt/big-file/5-GB-file
# head -1 /mnt/big*/*    
012345678901234567890123456789012345678901234567890123456789012
# head -1 /mnt/big*/* | wc -c
       64
#

So that's a copy rate of about 13 MB/s.

The second source partition was on dkc0:

pws500# ls -l
total 1049096
-rw-r--r--  1 root  wheel  1073741824 Jun  3 03:49 1-GB-file
pws500# sh
# for i in 1 2
>  do
>  /usr/bin/time cp * /mnt/big*
>  done
       113.46 real         0.03 user        25.43 sys
       114.10 real         0.03 user        24.94 sys
#

So, about 9 MB/s.

Copying from the ccd volume to dkc0 only achieved ~ 4 MB/s:

# ls -l
total 6817458
-rw-r--r--  1 root  wheel  1073741824 Mar 28 17:06 1-GB-file
-rw-r--r--  1 ray   wheel  5368709120 Mar 26 02:29 5-GB-file
-rw-r--r--  1 root  wheel   536870912 Jun  2 20:53 512-MB-file
-rw-r--r--  1 ray   wheel         335 Mar 29 10:43 p.c
# for i in 1 2 3 4 5
>  do
>  /usr/bin/time cp 1-* /usr/cp-tst
>  done
       250.39 real         0.03 user        24.92 sys
       252.69 real         0.03 user        24.89 sys
       252.92 real         0.03 user        25.23 sys
       252.62 real         0.02 user        24.91 sys
       252.64 real         0.03 user        24.87 sys
#


Ray