Newbie: What's this mean please.

[Simon Waters]

Just examining a test box I inherited with 2 identical SCSI disks ID0 and ID6 

Atlas Quantum v9's, on a 2940UW controllers.

Notice that "Goal" and "Curr" for ID6 are 20MB/s not the 40MB/s for ID0.

All the other settings everywhere I can find them (i.e. SCSIselect) seem to 
be identical.

Is this something to do with the controller hardware (if we still have 
documentation here it is hiding). Silly configuration choice. Confusion 
through meaningless numbers?

Notes: Debian 2.4.18 custom kernel (compiles in raid1 (and others), scsi, 
aic7xxx to avoid mysteries of initrd and modules with mirroring - but I think 
it did this before I touched it when it was running Redhat 7mumble), disks 
are a mirrored pair with 2 partitions / and swap. Running hdparm spits out 
"invalidate: busy buffer" a few times, and I've seem some other warnings, but 
these seem to 

Pointers to where I should have read first more than welcome.

I/O performance according to the tools I've tried isn't great, but then I'm 
not really sure how old all this hardware is, or what it should be able to do.

 Simon

Adaptec AIC7xxx driver version: 6.2.4
aic7880: Ultra Wide Channel A, SCSI Id=7, 16/253 SCBs
Channel A Target 0 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
        Goal: 40.000MB/s transfers (20.000MHz, offset 8, 16bit)
        Curr: 40.000MB/s transfers (20.000MHz, offset 8, 16bit)
        Channel A Target 0 Lun 0 Settings
                Commands Queued 1853
                Commands Active 0
                Command Openings 253
                Max Tagged Openings 253
                Device Queue Frozen Count 0
Channel A Target 1 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
Channel A Target 2 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
Channel A Target 3 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
Channel A Target 4 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
Channel A Target 5 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
Channel A Target 6 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)
        Goal: 20.000MB/s transfers (20.000MHz, offset 8)
        Curr: 20.000MB/s transfers (20.000MHz, offset 8)
        Channel A Target 6 Lun 0 Settings
                Commands Queued 1797
                Commands Active 0
                Command Openings 253
                Max Tagged Openings 253
                Device Queue Frozen Count 0
Channel A Target 7 Negotiation Settings
        User: 40.000MB/s transfers (20.000MHz, offset 255, 16bit)