[dm-devel] Way to get IO stats on multipath alias?

["Craig Simpson" <csimpson visto com>]

OK so I make my alias in /etc/multipath.conf
        multipath {
                wwid                    1HITACHI_750140820017
                alias                   asm13
        }


And as expected all 4 paths are there and happy in Hitachi's
active/passive world

asm13 (1HITACHI_750140820017) dm-44 HITACHI,DF600F
[size=32G][features=0][hwhandler=0]
\_ round-robin 0 [prio=2][active]
 \_ 1:0:0:17 sdbb 67:80   [active][ready]
 \_ 0:0:0:17 sdr  65:16   [active][ready]
\_ round-robin 0 [prio=0][enabled]
 \_ 0:0:1:17 sdcq 69:224  [active][ready]
 \_ 1:0:1:17 sded 128:80  [active][ready]

Now I can do a iostat -x and get the stats for sdbb, sdr, dscq, and
sded. 

But is there a way to collect statistics on asm13? 

Really need to know how it is doing on that level. Ya I can get info on
dm-44, but that changes across reboots, and could be different on
different nodes on the cluster.... 

Help!!!!

Craig