On 04/14/2016 12:31 PM, Nathan Scott wrote:
Hi Ken,
----- Original Message -----
From darkest Tibet ... well snowing and cold rather than dark.
Good to hear from you!
pmie could be taught to grok string valued expressions ... it would be a big
change in a lot of code that is tricky and a little brittle, but certainly
feasible.
OK.
I'd probably start by outlawing all the arithmetic functions (avg, sum) and
the relational operators (<, <=, >= and >) to avoid locale issues with
lexicographic order which takes out the min and max functions as well.
Even with these restrictions I think your use cases could all be handled.
Excellent.
If you can wait, I'll look in more earnest after I get back home in early
May.
Yes, it can certainly wait - thanks!
now that Ken is back ...
I've been thinking about this topic - not just for string valued metrics
(btw: hinv.map.scsi is another one in this class), but also for discrete
integer typed metrics, such as hinv.ndisk etc.
These metrics need to be logged more than "once"; rather more like "when
changed".
Once logged, they retain their discrete value (string or integer) until logged
again with a new value. As an alternative to pmie monitoring these metrics and
telling
pmlogger to log them again via pmlc, maybe pmlogger could just maintain a cache
(suitably indexed for efficiency) - when a discrete metric/instance/value with
logging
frequency of "when changed" changes, write it to the log again.
Regards
-- Mark
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