SATA Raid (stress test..)

[Alex Zbyslaw]

Beastie wrote:

>
> second tools is diskinfo, but i'm not quite happy with the result.
>
> #diskinfo -t /dev/amrd0s1d
> /dev/amrd0s1d
>        512             # sectorsize
>        999996609024    # mediasize in bytes (931G)
>        1953118377      # mediasize in sectors
>        121575          # Cylinders according to firmware.
>        255             # Heads according to firmware.
>        63              # Sectors according to firmware.
>
> Seek times:
>        Full stroke:      250 iter in   5.233346 sec =   20.933 msec
>        Half stroke:      250 iter in   3.828152 sec =   15.313 msec
>        Quarter stroke:   500 iter in   6.232849 sec =   12.466 msec
>        Short forward:    400 iter in   2.409001 sec =    6.023 msec
>        Short backward:   400 iter in   2.594473 sec =    6.486 msec
>        Seq outer:       2048 iter in   0.638372 sec =    0.312 msec
>        Seq inner:       2048 iter in   0.671994 sec =    0.328 msec
> Transfer rates:
>        outside:       102400 kbytes in   1.102065 sec =    92916 
> kbytes/sec
>        middle:        102400 kbytes in   1.209657 sec =    84652 
> kbytes/sec
>        inside:        102400 kbytes in   1.912485 sec =    53543 
> kbytes/sec

Why not happy?  Transfer rates from 53 to 92Mb/s, give or take; what's 
wrong with that?  On a plain sata disk I get:

Seek times:
        Full stroke:      250 iter in   4.717248 sec =   18.869 msec
        Half stroke:      250 iter in   5.342099 sec =   21.368 msec
        Quarter stroke:   500 iter in   8.870424 sec =   17.741 msec
        Short forward:    400 iter in   2.753187 sec =    6.883 msec
        Short backward:   400 iter in   1.390941 sec =    3.477 msec
        Seq outer:       2048 iter in   0.426796 sec =    0.208 msec
        Seq inner:       2048 iter in   0.487280 sec =    0.238 msec
Transfer rates:
        outside:       102400 kbytes in   1.652736 sec =    61958 kbytes/sec
        middle:        102400 kbytes in   1.697364 sec =    60329 kbytes/sec
        inside:        102400 kbytes in   1.834759 sec =    55811 kbytes/sec

A second, different, disk gives me better seek times but roughly similar 
transfer rates.  So I beat your inside transfer rate, but you're 50% up 
on the outside rate.

If you have windows anywhere, then download sandra-lite.  Among other 
things, it has comparison benchmarks for all its tests, including disk 
transfer rates for things like SCSI-RAID0, RAID1, SATA/PATA-RAID0/1 etc.

--Alex