Fix iostat watcher weirdness

[GoogleCodeExporter]

mogstored uses `iostat` to report back some data for mogilefs and for the user 
about how busy its devices are.

The methods it uses to transport this data are convoluted and abstract; meaning 
a user cannot easily tell if a device is idle or if 'iostat' isn't even 
installed.

It should be overhauled so errors are easily discoverable/testable (due to 
iostat missing, different formats used, etc). mogadm check should be able to 
display 'NA' instead of '0' if reading this data is broken.

Original issue reported on code.google.com by dorma...@rydia.net on 20 Sep 2010 at 12:34

[GoogleCodeExporter]

> On server with part of disks (dev2*):
> %iostat -dx 1 30
>                         extended device statistics
> device     r/s   w/s    kr/s    kw/s wait svc_t  %b
> ad10       4.7   1.5    61.2    19.9    1  15.3   3
> ad12      15.6   2.5   714.5   150.7    0   8.7  11
> ad14       4.8   3.0   384.6   220.9    0   2.7   1
> ad16       5.3   3.0   422.4   222.1    0   2.7   1
>
>
> Maybe thats because of iostat reporting in another format in FreeBSD
> than in Linux (i'm running FreeBSD 8.0) ?

Uhm, yeah the format's pretty different.

$ iostat -dx 1 30
Linux 2.6.32.6 (d)      04/20/10        _x86_64_        (2 CPU)

Device:         rrqm/s   wrqm/s     r/s     w/s   rsec/s   wsec/s avgrq-sz
avgqu-sz   await  svctm  %util
sda               0.00     1.24    0.38    0.74    13.65    15.83    26.23
0.01    5.88   0.20   0.02

Device:         rrqm/s   wrqm/s     r/s     w/s   rsec/s   wsec/s avgrq-sz
avgqu-sz   await  svctm  %util
sda               0.00     0.00    0.00    0.00     0.00     0.00     0.00
0.00    0.00   0.00   0.00

Original comment by dorma...@rydia.net on 3 Oct 2010 at 12:44

Attachments:

• io.txt

[GoogleCodeExporter]

pretty sure eric just fixed this. closing out.

Original comment by dorma...@rydia.net on 12 Aug 2012 at 10:59

• Changed state: Fixed