Re: Add --human flag to slabtop

Hi Craig,

thanks for merging that. Sorry I forgot to update NEWS and manpage.

I'd also like to upgrade vmstat - I'd like `bi`, `bo`, `in`, `cs` fields
to not mangle the rest of columns. See the end of e-mail (Supplement 1) for=
 en example
of a garbled output on a big server.

I wonder what's the best idea:

- make `--wide` even wider

- make `vmstat` cooperate with `column -t` - `vmstat 1 5  | column -t`
  gives prettier results than `vmstat --wide` except it's not real-time

- add an extra switch (--unit-io) for bi/bo and an extra switch for
  system (--unit-system)...

- make `-SM` to apply to bi, bo, in, cs as well.

Minor nitpick - Currently, the docs on `-S` say

>  Note this does not change the block (bi/bo) fields, which are always mea=
sured in blocks.

which for the current code should be reworded to

>  Note this changes only memory and swap sections.

- reorder the troublesome columns to the end of the output - `cpu`
  section is actually the most well-behaved because the values are
  bounded. If we put it next to `procs`, noise introduced by big numbers
  in io/system sections won't have that much of an effect.

  See Supplement 2 for example, which is the same data as at the end of the
  e-mail but "cpu" was shuffled to the left. I like it more than the
  original output, but there's still a problem of tracing spikes in the
  unaligned columns (i.e. it's not trivial to see if there was a period
  when `cs` or `in` showed 10x the normal value)



We need to keep in mind that running vmstat on busy, multi-cpu machine
for extended period of time (vmstat 60) will inflate the counters even
more. The example below is for 48-logical-cpu box. I think to plan for
the future, vmstat should make the table readable for 500-core box, ran
at 60s interval, so we should budget for at least 3 extra orders of
magnitude to the example output below.

Can you please suggest the best solution here?
Thanks,
Kris


Supplement 1: example output on a 48-core server
[email protected]:~# vmstat -SM --wide 1
--procs-- -----------------------memory---------------------- ---swap-- ---=
--io---- -system-- --------cpu--------
   r    b         swpd         free         buff        cache   si   so    =
bi    bo   in   cs  us  sy  id  wa  st
   2    1            0       177010            1        42988    0    0    =
44  5877    0    0  10   5  78   7   0
   3    1            0       177027            1        42988    0    0    =
75  2392 30138 38917   3   1  94   2   0
   0    1            0       177026            1        42988    0    0    =
86  2080 27563 30582   4   1  93   2   0
   5    2            0       177307            1        42988    0    0    =
43 1685248 33485 47178   2   7  88   3   0
   0    2            0       176895            1        42988    0    0    =
22 1820964 35203 65599   2   4  89   4   0
   1    0            0       177004            1        42988    0    0    =
21 126812 34613 57499   3   2  93   2   0
   2    0            0       177007            1        42988    0    0    =
 0   280 30083 35506   4   2  95   0   0
   2    0            0       177011            1        42988    0    0    =
 0     0 34153 34912   2   1  96   0   0
   3    1            0       177268            1        42988    0    0    =
 0 1613456 31176 41964   2   7  90   1   0
^c

Supplement 2: reordered columns for readability
[email protected]:~# vmstat -SM --wide 1
--procs-- --------cpu-------- -----------------------memory----------------=
------ ---swap-- -----io---- -system--   =20
   r    b  us  sy id  wa  st         swpd         free         buff        =
cache   si   so    bi    bo   in   cs    =20
   2    1  10  5  78   7   0            0       177010            1        =
42988    0    0    44  5877    0    0    =20
   3    1  3   1  94   2   0            0       177027            1        =
42988    0    0    75  2392 30138 38917  =20
   0    1  4   1  93   2   0            0       177026            1        =
42988    0    0    86  2080 27563 30582  =20
   5    2  2   7  88   3   0            0       177307            1        =
42988    0    0    43 1685248 33485 47178=20
   0    2  2   4  89   4   0            0       176895            1        =
42988    0    0    22 1820964 35203 65599=20
   1    0  3   2  93   2   0            0       177004            1        =
42988    0    0    21 126812 34613 57499 =20
   2    0  4   2  95   0   0            0       177007            1        =
42988    0    0     0   280 30083 35506  =20
   2    0  2   1  96   0   0            0       177011            1        =
42988    0    0     0     0 34153 34912  =20
   3    1  2   7  90   1   0            0       177268            1        =
42988    0    0     0 1613456 31176 41964=20
^C