Parsing iostat output

Question

the output of iostat is like that:

Device:         rrqm/s   wrqm/s   r/s   w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await  svctm  %util
sda               0.00     2.40  0.01  3.92     0.16    25.28    12.95     0.05   12.81   6.58   2.58
sda1              0.00     0.00  0.00  0.00     0.00     0.00    25.86     0.00    6.57   5.38   0.00
sda2              0.00     2.40  0.01  3.92     0.16    25.28    12.95     0.05   12.81   6.58   2.58
sdb               0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00   30.37  20.16   0.00
VG00-LogVol00
               0.00     0.00  0.00  0.70     0.02     2.79     8.04     0.02   23.72   3.71   0.26
VG00-LogVol04
               0.00     0.00  0.00  4.31     0.03    17.26     8.01     0.07   16.74   4.32   1.87
VG00-LogVol03
               0.00     0.00  0.00  0.24     0.00     0.98     8.01     0.01   21.37   8.52   0.21
VG00-LogVol08
               0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00   14.03   2.31   0.00
VG00-LogVol01
               0.00     0.00  0.00  0.00     0.00     0.00     8.03     0.00  127.25   1.17   0.00
VG00-LogVol07
               0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00    2.42   1.72   0.00
VG00-LogVol06
               0.00     0.00  0.00  0.80     0.01     3.21     8.02     0.01   10.28   4.89   0.39
VG00-LogVol02
               0.00     0.00  0.01  0.26     0.10     1.04     8.52     0.01   52.88   6.01   0.16
VG00-LogVol05
               0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00    3.73   0.33   0.00

I try to parse the output but when I reach "VG00-LogVol00", "VG00-LogVol04" I have problems parsing the text. Is there a way to remove the extra lines using sed?

Thank you

score 1 · Accepted Answer · answered Feb 19 '13 at 09:54

If VG00 is always present in split lines, you could do it like this:

sed '/VG00/ { N; s/\n// }'

With the copy/pasted text I have the following aligns the columns (GNU sed and BSD sed):

sed '/VG00/ { N; s/\n//; s/ \{5,\}/     /; }'

Output:

Device:         rrqm/s   wrqm/s   r/s   w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await  svctm  %util
sda               0.00     2.40  0.01  3.92     0.16    25.28    12.95     0.05   12.81   6.58   2.58
sda1              0.00     0.00  0.00  0.00     0.00     0.00    25.86     0.00    6.57   5.38   0.00
sda2              0.00     2.40  0.01  3.92     0.16    25.28    12.95     0.05   12.81   6.58   2.58
sdb               0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00   30.37  20.16   0.00
VG00-LogVol00     0.00     0.00  0.00  0.70     0.02     2.79     8.04     0.02   23.72   3.71   0.26
VG00-LogVol04     0.00     0.00  0.00  4.31     0.03    17.26     8.01     0.07   16.74   4.32   1.87
VG00-LogVol03     0.00     0.00  0.00  0.24     0.00     0.98     8.01     0.01   21.37   8.52   0.21
VG00-LogVol08     0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00   14.03   2.31   0.00
VG00-LogVol01     0.00     0.00  0.00  0.00     0.00     0.00     8.03     0.00  127.25   1.17   0.00
VG00-LogVol07     0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00    2.42   1.72   0.00
VG00-LogVol06     0.00     0.00  0.00  0.80     0.01     3.21     8.02     0.01   10.28   4.89   0.39
VG00-LogVol02     0.00     0.00  0.01  0.26     0.10     1.04     8.52     0.01   52.88   6.01   0.16
VG00-LogVol05     0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00    3.73   0.33   0.00

score 0 · Answer 2 · answered Feb 19 '13 at 09:59

0

I'd go for

sed -e '/^\([^[:space:]]\+\)$/{N;s/\n//;}'

assuming the device lines have no whitespace.

But I'd also look into the possibility to influence iostat and make it produce different output. I don't know the options there, though.

answered Feb 19 '13 at 09:59

Michael Krelin - hacker

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iostat unfortunately doesn't have such outputs :( – amprantino Feb 19 '13 at 10:19

Parsing iostat output

2 Answers2