Simon Burge writes:
> Is RAIDframe meant do load balancing across submirrors? 

Yes, it does/tries to.  

> It doesn't
> appear to - this is running a big du:

A single du likely isn't going to balance very well.  2 du's (started
a few seconds apart) or two reads from two different (and large) files
should balance much better...  Basically a single du isn't giving RAIDframe
enough work to do any real balancing.

See rf_SelectMirrorDiskIdle() in sys/dev/raidframe/rf_dagfuncs.c for 
where/how it's done.
 
> thoreau:~ 1528> iostat raid0 wd0 wd1 5 10
>       tty            wd0             wd1           raid0             cpu
>  tin tout  KB/t t/s MB/s   KB/t t/s MB/s   KB/t t/s MB/s  us ni sy in id
>    1  356  6.43  19 0.12   7.61   6 0.05   6.71  26 0.17   2  0  1  0 97
>    2  242  5.78 100 0.57   6.17  29 0.17   5.87 129 0.74   2  0  8  1 89
>    0  489  5.63 115 0.63   4.88  20 0.09   5.52 134 0.73  10  0 16  1 72
>    0  339  6.45 147 0.93   7.61  58 0.43   6.77 205 1.36   1  0  4  1 94
>    0  147  5.81 138 0.78   6.48  26 0.16   5.92 164 0.95   1  0  6  1 92
>    0  328  5.80 147 0.83   7.16  30 0.21   6.03 177 1.04   1  0  6  1 91
>    0  278  6.80 143 0.95   7.81  64 0.49   7.11 207 1.44   1  0  4  1 94
>    0   85  6.26 168 1.03   7.87  56 0.43   6.66 224 1.45   1  0  5  1 93
>    0  175  5.90 148 0.85   6.75  21 0.14   6.00 169 0.99   1  0  6  1 92
>    0  344  5.94 160 0.93   7.77  30 0.23   6.23 190 1.15   1  0  7  1 91
> 
> Simon.
> --
> Simon Burge                            <simonb@wasabisystems.com>
> NetBSD Sales, Support and Service:  http://www.wasabisystems.com/

Later...

Greg Oster