siis/atacam/ata/gmirror 8.0-BETA3 disk performance

[Derek (freebsd lists)]

James R. Van Artsdalen wrote:
> Derek (freebsd lists) wrote:
>> I get about 40MB/s read, and 30MB/s write.  See attached
>> bench-*.txt files.
> 
> That's too slow.  As I posted on July 31 I got sustained read rates of
> 875 MB/s across ten disks, through two 3124 cards and four port multipliers.
> 

Right, so directly to a single disks I see 40/30MB/s read/write 
respectively. "Benchmarks" on the Internet peg the i/o to be 
around 100/80MB/s average read on these disks.

> The system I tested was a dual processor Opteron 244 (1.8 GHz) running
> amd64.  Perhaps more important, my disk controllers were on two
> different PCI-X buses with ample bandwidth (100 MHz 64-bit and 133 MHz
> 64-bit).

 From the dmesg, this is a dual 1.4Ghz P3, and the controller is 
standard 32-bit/33Mhz PCI.  Mind you, I think even 80MB/s should 
not saturate the PCI bus, if there's nothing else going on.

> Is your disk controller on a PCI bus, and is there any other PCI traffic
> at the time?

The only traffic would be a little ssh traffic on fxp0, but 
otherwise, I can't think of any other traffic that would be 
occurring.

- Derek