[collectd] swap plugin improvements

[Aurélien Reynaud]

Hello Florian,


Le mercredi 06 octobre 2010 à 11:43 +0200, Florian Forster a écrit :
> 
> sorry for the very delayed reply. Fortunately I've kept track of this
> patch in the version 5.0 wiki page, otherwise I would have forgotten
> about it.
> Okay, if I understand you correctly, then "-l" reports the swap usage
> from the device's perspective while "-s" uses the point of view from
> virtual memory.

Exactly.

> I think either view has its advantages, so I think the best way to go is
> to let the user chose what to see. I can't really think if a clever name
> for the config option though. What do you think about "ReportPhysical" /
> "ReportVirtual"? (Setting both to true will result in both views being
> collected.)

In my original posting, I suggested moving the "-s" (virtual memory) to
the vmem plugin which is currently linux-only. Don't you think this
would make sense?

> 
> With regard to the physical view: Would it make sense to report this on
> a per-disk (per-partition) basis? For example:
> 
> > root at uv8801xr:/root> swap -l
> > swapfile             dev  swaplo blocks   free
> > /dev/vx/dsk/swapvol 242,5      16 24576704 23138752
> 
> This could be reported as
> 
>   uv8801xr/swap-vx-dsk-swapvol/swap-used = 24576704 - 23138752
>   uv8801xr/swap-vx-dsk-swapvol/swap-free = 23138752
> 
> We could possibly configurate this behavior with something like
>   ReportPhysical no/yes/separate/combined
> where "yes" and "combined" are synonymous.

Sounds reasonable to be, as long as "combined" is the default. The total
values are what IT execs and developers are interested in. The exact
physical layout of swap is for admins fine-tuning their systems...

By the way, I also use collectd for producing monthly reports and
capacity planning (headed to decision makers rather than technicians)!


Regards,

Aurélien Reynaud