changes in iostat output in 11.x vs 10.x

[Miroslav Lachman]

I upgraded one of our servers from 10.4 to 11.2 and scripts using output 
of "iostat -x" are not working anymore.
A checked the output of iostat and it is different.

# on 10.4

# iostat -w 5 -c 2 -x ada0 ada1
                         extended device statistics
device     r/s   w/s    kr/s    kw/s qlen svc_t  %b
ada0      51.5  28.3  1381.4   539.7    0   9.7  33
ada1      51.4  28.2  1381.5   539.7    0  10.1  34
                         extended device statistics
device     r/s   w/s    kr/s    kw/s qlen svc_t  %b
ada0       0.2   6.4     2.4   136.5    0   2.9   2
ada1       0.0   5.8     0.0   136.5    0   3.4   2


# on 11.2

# iostat -w 5 -c 2 -x ada0 ada1
                         extended device statistics
device       r/s     w/s     kr/s     kw/s  ms/r  ms/w  ms/o  ms/t qlen  %b
ada0           6      24     35.9    697.9     2     1    77     3    0   6
ada1           6      23     34.9    697.9     2     1    77     3    0   6
                         extended device statistics
device       r/s     w/s     kr/s     kw/s  ms/r  ms/w  ms/o  ms/t qlen  %b
ada0           0      21      0.0    776.6     0     0    96     2    0   5
ada1           0      21      0.0    776.6     0     0   100     2    0   5

But I cannot find the explanation of new columns. The manpage seems the 
same for 10.4 and 11.2

    The extended	iostat device display, with the	-x flag	specified,
    shows the following statistics:

    r/s	   read	operations per second
    w/s	   write operations per	second
    kr/s	   kilobytes read per second
    kw/s	   kilobytes write per second
    qlen	   transactions	queue length
    svc_t   average duration of transactions, in	milliseconds
    %b	   % of	time the device	had one	or more	outstanding transac-
	   tions

But there is no svc_t column anymore and there are ms/r ms/w ms/o and 
ms/t columns not mentioned in man page.

Is it a documentation bug?

Is ms/t the same what was previously known as svc_t?

Kind regards
Miroslav Lachman