From a15fcac1b68283a0b409cd83e20771c842d5fcbd Mon Sep 17 00:00:00 2001 From: hagen1778 Date: Thu, 21 Nov 2024 16:30:59 +0100 Subject: [PATCH] docs: update differences between vmagent and Prometheus in FAQ * mention stream aggregation * rm statement that Prometheus can only pull data, which is not true anymore * mention absence of backfilling limitations Signed-off-by: hagen1778 --- docs/FAQ.md | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/docs/FAQ.md b/docs/FAQ.md index a9a12e5b5..2791a2a2f 100644 --- a/docs/FAQ.md +++ b/docs/FAQ.md @@ -53,7 +53,7 @@ and send data to multiple remote storage systems, vmagent has the following addi * vmagent usually requires lower amounts of CPU, RAM and disk IO compared to Prometheus when scraping an enormous number of targets (more than 1000) or targets with a great number of exposed metrics. -* vmagent provides independent disk-backed buffers for each configured remote storage (see `-remoteWrite.url`). This means that slow or temporarily unavailable storage +* vmagent provides independent [disk-backed buffers](https://docs.victoriametrics.com/vmagent/#calculating-disk-space-for-persistence-queue) for each configured remote storage (see `-remoteWrite.url`). This means that slow or temporarily unavailable storage doesn't prevent it from sending data to healthy storage in parallel. Prometheus uses a single shared buffer for all the configured remote storage systems (see `remote_write->url`) with a hardcoded retention of 2 hours. * vmagent may accept, relabel and filter data obtained via multiple data ingestion protocols in addition to data scraped from Prometheus targets. @@ -76,13 +76,15 @@ and send data to multiple remote storage systems, vmagent has the following addi Both [vmagent](https://docs.victoriametrics.com/vmagent/) and [Prometheus agent](https://prometheus.io/blog/2021/11/16/agent/) serve the same purpose – to efficiently scrape Prometheus-compatible targets at the edge. They have the following differences: * vmagent usually requires lower amounts of CPU, RAM and disk IO compared to the Prometheus agent. -* Prometheus agent supports only pull-based data collection (e.g. it can scrape Prometheus-compatible targets), while vmagent supports both pull and push data collection – it can accept data via many popular data ingestion protocols such as InfluxDB line protocol, Graphite protocol, OpenTSDB protocol, DataDog protocol, Prometheus protocol, CSV and JSON – see [these docs](https://docs.victoriametrics.com/vmagent/#features). +* vmagent supports both pull and push data collection – it can accept data via many popular data ingestion protocols such as InfluxDB line protocol, Graphite protocol, OpenTSDB protocol, DataDog protocol, Prometheus protocol, OpenTelemetry metrics protocol, CSV and JSON – see [these docs](https://docs.victoriametrics.com/vmagent/#features). +* vmagent doesn't have limitations on backfilling of historical data. * vmagent can easily scale horizontally to multiple instances for scraping a big number of targets – see [these docs](https://docs.victoriametrics.com/vmagent/#scraping-big-number-of-targets). * vmagent supports [improved relabeling](https://docs.victoriametrics.com/vmagent/#relabeling). * vmagent can limit the number of scraped metrics per target – see [these docs](https://docs.victoriametrics.com/vmagent/#cardinality-limiter). * vmagent supports loading scrape configs from multiple files – see [these docs](https://docs.victoriametrics.com/vmagent/#loading-scrape-configs-from-multiple-files). * vmagent supports data reading and data writing from/to Kafka – see [these docs](https://docs.victoriametrics.com/vmagent/#kafka-integration). * vmagent can read and update scrape configs from http and https URLs, while the Prometheus agent can read them only from the local file system. +* vmagent supports [stream aggregation](https://docs.victoriametrics.com/stream-aggregation/) feature for performing aggregates on collected or received samples before sending them to remote storage. ## Is it safe to enable [remote write](https://prometheus.io/docs/operating/integrations/#remote-endpoints-and-storage) in Prometheus?