Thanos automatically deals with downsample lookback with no changes. This was fixed at least 2 years ago.
On Mon, Nov 15, 2021, 18:54 Julien Pivotto <[email protected]> wrote: > We are willing to have downsampling in Prometheus too in the future. > > I would merge that pull request. > > Le lun. 15 nov. 2021, 15:19, Vilius Pranckaitis <[email protected]> > a écrit : > >> *TL;DR*: ability to set a custom lookback delta for a query would be >> useful when time series have drastically different resolutions. >> >> --- >> >> Currently, Prometheus allows configuring lookback delta through >> configuration flag. This works well if the resolutions/scrape intervals of >> time series are similar, but is inconvenient if they differ a lot. E.g. if >> we had two time series, one with a datapoint each hour and another one with >> a datapoint each minute, a lookback of 2h would work for the first one, but >> would be way too big for the second one. >> >> This impacts looking at downsampled data greater than 5 minutes (the >> default lookback period) which both Thanos and M3 frequently keep >> (depending on user configuration). Both support downsampling data to user >> configured resolutions, thus lookback delta should be selected according to >> what resolution is being queried when querying downsampled data. Both >> Thanos and M3 depend on Prometheus and use `promql.Engine` for executing >> queries, which doesn't allow setting custom lookback for a particular query. >> >> While I understand that this might be more relevant for M3 and Thanos >> than for Prometheus, just wanted to check what the maintainers of >> Prometheus think about this. If this seems useful, someone from M3 should >> be able to submit a PR (we have already looked at the code and it doesn't >> look like it needs huge changes). >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Prometheus Developers" 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-developers/84c03b13-25d7-479c-b678-44cd8625f2c0n%40googlegroups.com >> <https://groups.google.com/d/msgid/prometheus-developers/84c03b13-25d7-479c-b678-44cd8625f2c0n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "Prometheus Developers" 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-developers/CAFJ6V0p-_k_Yjy_gUdvHaogxZz%3D7DeNEMM7zz7uBYD%2BYBA%2B6bw%40mail.gmail.com > <https://groups.google.com/d/msgid/prometheus-developers/CAFJ6V0p-_k_Yjy_gUdvHaogxZz%3D7DeNEMM7zz7uBYD%2BYBA%2B6bw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Prometheus Developers" 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-developers/CABbyFmrjPhnrWFm441MnH86qVy1mxhE4U8F6ZDPt8Hg-oRjEsA%40mail.gmail.com.
