On 21 Feb 07:31, Stuart Clark wrote: > On 21/02/2023 03:29, Christoph Anton Mitterer wrote: > > Hey. > > > > I wondered whether one can to with Prometheus something similar that is > > possible with systems using RRD (e.g. Ganlia). > > > > Depending on the kind of metrics, like for those from the node exporter, > > one may want a very high sample resolution (and thus short scraping > > interval) for like the last 2 days,... but the further one goes back the > > less interesting those data becomes, at least in that resolution (ever > > looked a how much IO a server had 2 years ago per 15s)? > > > > What one may however want is a rough overview of these metrics for those > > time periods longer ago, e.g. in order to see some trends. > > > > > > For other values, e.g. the total used disk space on a shared filesystem > > or maybe a tape library, one may not need such high resolution for the > > last 2 days, but therefore want the data (with low sample resolution, > > e.g. 1 sample per day) going back much longer, like the last 10 years. > > > > > > With Ganglia/RRD it one would then simply use multiple RRDs, each for > > different time spans and with different resolutions... and RRD would > > interpolate it's samples accordingly. > > > > > > Can anything like this be done with Prometheus? Or is that completely > > out of scope? > > > > > > I saw that one can set the retention period, but that seems to affect > > everything. > > > > So even if I have e.g. my low resolution tape library total size, which > > I could scrape only every hour or so, ... it wouldn't really help me. > > In order to keep data for that like the last 10 years, I'd need to set > > the retention time to that. > > > > But then the high resolution samples like from the node exporter would > > also be kept that long (with full resolution). > > > Prometheus itself cannot do downsampling, but other related projects such as > Cortex & Thanos have such features.
We would love to have this in the future but it would require careful planning and design document. -- Julien Pivotto @roidelapluie -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/prometheus-users/Y/SgxLFrcQ4fL0mo%40nixos.
