The 'Ganglia GMond Python Modules' wiki page has some incorrect guidance on it, as far as I can tell.
And incorrect official docs are very confusing for us poor users trying to get our heads around things.
It states:
value_threshold: If your metric reports a value above the value (in the units defined in your metric descriptor) defined here, it will be reported to Ganglia regardless of the 'time_threshold' defined for the collection_group
while the gmond.conf man page states:
Each time the metric value is collected the new value is compared with the old value collected. If the difference between the last value and the current value is greater than the value_threshold, the entire collection group is send to the udp_send_channels defined.
It's important to note that all metrics in a collection group are sent even when only a single value_threshold is surpassed.
I haven't looked through the code to check, but the gmond.conf version of things (difference since last measurement threshold not greater-than threshold) makes more sense in the context of when Ganglia would like to start reporting values more rapidly, i.e. at times of rapid change.
Hi,
The 'Ganglia GMond Python Modules' wiki page has some incorrect guidance on it, as far as I can tell. And incorrect official docs are very confusing for us poor users trying to get our heads around things.
It states:
while the gmond.conf man page states:
I haven't looked through the code to check, but the gmond.conf version of things (difference since last measurement threshold not greater-than threshold) makes more sense in the context of when Ganglia would like to start reporting values more rapidly, i.e. at times of rapid change.
thanks, Hamish