Re: [pcp] Calculated/derived metrics?

[Marko Myllynen <myllynen@xxxxxxxxxx>]

Hi,

On 2015-05-08 01:45, Ken McDonell wrote:
> On 08/05/15 06:35, Frank Ch. Eigler wrote:
>> ...
>> Is the rate() derived-metrics function applicable here?
> 
> If I understand Marko's requirement he'd like to get something close to
> the I/O rate of the process over its life, rather than over the last
> time period (hotproc.io.write_bytes by itself will give you the latter,
> as will rate(hotproc.io.write_bytes) in a derived metric).

yes, I think there are certainly use cases for both, in this particular
case I was thinking checking e.g. with pmval or pmdumptext "hot"
processes' I/O activity for an application which does its I/O in bursts,
with rate() most often the result would be zero but with value() it'd
give instantly some sort of general idea what app has been up to
I/O-wise (so it'd be a perfect match for this derived convenience metric).

Thanks,

-- 
Marko Myllynen