Adding upstream version 1.29.3.upstream/1.29.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 72 insertions, 0 deletions

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+<!--
+title: "Change how long Netdata stores metrics"
+description: "With a single configuration change, the Netdata Agent can store days, weeks, or months of metrics at its famous per-second granularity."
+custom_edit_url: https://github.com/netdata/netdata/edit/master/docs/store/change-metrics-storage.md
+-->
+
+# Change how long Netdata stores metrics
+
+import { Calculator } from '../../src/components/agent/dbCalc/'
+
+The [database engine](/database/engine/README.md) uses RAM to store recent metrics. When metrics reach a certain age,
+and based on how much system RAM you allocate toward storing metrics in memory, they are compressed and "spilled" to
+disk for long-term storage.
+
+The default settings retain about two day's worth of metrics on a system collecting 2,000 metrics every second, but the
+Netdata Agent is highly configurable if you want your nodes to store days, weeks, or months worth of per-second data.
+
+The Netdata Agent uses two settings in `netdata.conf` to change the behavior of the database engine:
+
+```conf
+[global]
+    page cache size = 32
+    dbengine multihost disk space = 256
+```
+
+`page cache size` sets the maximum amount of RAM (in MiB) the database engine uses to cache and index recent metrics.
+`dbengine multihost disk space` sets the maximum disk space (again, in MiB) the database engine uses to store
+historical, compressed metrics. When the size of stored metrics exceeds the allocated disk space, the database engine
+removes the oldest metrics on a rolling basis.
+
+## Calculate the system resources (RAM, disk space) needed to store metrics
+
+You can store more or less metrics using the database engine by changing the allocated disk space. Use the calculator
+below to find an appropriate value for `dbengine multihost disk space` based on how many metrics your node(s) collect,
+whether you are streaming metrics to a parent node, and more.
+
+You do not need to edit the `page cache size` setting to store more metrics using the database engine. However, if you
+want to store more metrics _specifically in memory_, you can increase the cache size.
+
+> ⚠️ This calculator provides an estimate of disk and RAM usage for **metrics storage**, along with its best
+> recommendation for the `dbengine multihost disk space` setting. Real-life usage may vary based on the accuracy of the
+> values you enter below, changes in the compression ratio, and the types of metrics stored.
+
+<Calculator />
+
+## Edit `netdata.conf` with recommended database engine settings
+
+Now that you have a recommended setting for `dbengine multihost disk space`, open `netdata.conf` with
+[`edit-config`](/docs/configure/nodes.md#use-edit-config-to-edit-configuration-files) and look for the `dbengine
+multihost disk space` setting. Change it to the value recommended above. For example:
+
+```conf
+[global]
+    dbengine multihost disk space = 1024
+```
+
+Save the file and restart the Agent with `service netdata restart` to change the database engine's size.
+
+## What's next?
+
+For more information about the database engine, see our [database reference doc](/database/engine/README.md).
+
+Storing metrics with the database engine is completely interoperable with [exporting to other time-series
+databases](/docs/export/external-databases.md). With exporting, you can use the node's resources to surface metrics
+when [viewing dashboards](/docs/visualize/interact-dashboards-charts.md), while also archiving metrics elsewhere for
+further analysis, visualization, or correlation with other tools. 
+
+If you don't want to always store metrics on the node that collects them or run ephemeral nodes without dedicated
+storage, you can use [streaming](/streaming/README.md). Streaming allows you to centralize your data, run Agents as
+headless collectors, replicate data, and more.
+
+[![analytics](https://www.google-analytics.com/collect?v=1&aip=1&t=pageview&_s=1&ds=github&dr=https%3A%2F%2Fgithub.com%2Fnetdata%2Fnetdata&dl=https%3A%2F%2Fmy-netdata.io%2Fgithub%2Fdocs%2Fstore%2Fchange-metrics-storage&_u=MAC~&cid=5792dfd7-8dc4-476b-af31-da2fdb9f93d2&tid=UA-64295674-3)](<>)