From 3638e096f3785c4177c5e1d6ec1a3f35b6695cab Mon Sep 17 00:00:00 2001 From: Yurii Kravets <30324382+YuriKravetc@users.noreply.github.com> Date: Mon, 20 Dec 2021 13:43:04 +0200 Subject: [PATCH] Update FAQ.md (#1765) * Update FAQ.md Adding explanation "Why do same metrics have differences in VictoriaMetrics and Prometheus dashboards?" * Update FAQ * Update FAQ.md * Apply suggestions from code review Co-authored-by: Roman Khavronenko Co-authored-by: Aliaksandr Valialkin Co-authored-by: Roman Khavronenko --- docs/FAQ.md | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/docs/FAQ.md b/docs/FAQ.md index d7b63115b3..61d068a679 100644 --- a/docs/FAQ.md +++ b/docs/FAQ.md @@ -330,3 +330,11 @@ Please see [these docs](https://docs.victoriametrics.com/vmctl.html#migrating-da ## How to migrate data from Graphite to VictoriaMetrics? Please use [whisper-to-graphite](https://github.com/bzed/whisper-to-graphite) tool for reading the data from Graphite and pushing it to VictoriaMetrics via [Graphite import API](https://docs.victoriametrics.com/#how-to-send-data-from-graphite-compatible-agents-such-as-statsd). + + +## Why do same metrics have differences in VictoriaMetrics and Prometheus dashboards? + +There could be a slight difference in stored values for time series. Due to different compression algorithms, VM may reduce precision for float values with more than 12 significant decimal digits. Please see [this article](https://valyala.medium.com/evaluating-performance-and-correctness-victoriametrics-response-e27315627e87) + +The query engine may behave differently for some functions. Please see [this article](https://medium.com/@romanhavronenko/victoriametrics-promql-compliance-d4318203f51e) +