Docs: Add strategies topic (#26103)

* Create use.md

* Update timeseries.md

* changed file name and added content

* Update menu.yaml

* Update strategies.md

docs/sources/getting-started/strategies.md

++++
+title = "Monitoring strategies"
+description = "Common monitoring strategies"
+keywords = ["grafana", "intro", "guide", "concepts", "methods"]
+type = "docs"
+[menu.docs]
+weight = 500
++++
+
+# Common observability strategies
+
+When you have a lot to monitor, like a server farm, you need a strategy to decide what is important enough to monitor. This page describes several common methods for choosing what to monitor.
+
+A logical strategy allows you to make uniform dashboards and scale your observability platform more easily.
+
+## Guidelines for usage
+
+- The USE method tells you how happy your machines are, the RED method tells you how happy your users are.
+- USE reports on causes of issues. 
+- RED reports on user experience and is more likely to report symptoms of problems.
+- The best practice of alerting is to alert on symptoms rather than causes, so alerting should be done on RED dashboards.
+
+## USE method
+
+USE stands for:
+
+- **Utilization -** Percent time the resource is busy, such as node CPU usage
+- **Saturation -** Amount of work a resource has to do, often queue length or node load
+- **Errors -** Count of error events
+
+This method is best for hardware resources in infrastructure, such as CPU, memory, and network devices. For more information, refer to [The USE Method](http://www.brendangregg.com/usemethod.html).
+
+## RED method
+
+RED stands for:
+
+- **Rate -** Requests per second
+- **Errors -** Number of requests that are failing
+- **Duration -** Amount of time these requests take, distribution of latency measurements
+
+This method is most applicable to services, especially a microservices environment. For each of your services, instrument the code to expose these metrics for each component. RED dashboards are good for alerting and SLAs. A well-designed RED dashboard is a proxy for user experience.
+
+For more information, refer to Tom Wilkie's blog post [The RED method: How to instrument your services](https://grafana.com/blog/2018/08/02/the-red-method-how-to-instrument-your-services).
+
+## The Four Golden Signals
+
+According to the [Google SRE handbook](https://landing.google.com/sre/sre-book/chapters/monitoring-distributed-systems/#xref_monitoring_golden-signals), if you can only measure four metrics of your user-facing system, focus on these four.
+
+This method is similar to the RED method, but it includes saturation.
+
+- **Latency -** Time taken to serve a request
+- **Traffic -** How much demand is placed on your system
+- **Errors -** Rate of requests that are failing
+- **Saturation -** How "full" your system is

docs/sources/getting-started/timeseries.md

@@ -3,8 +3,8 @@ title = "Time series"
 description = "Introduction to time series"
 keywords = ["grafana", "intro", "guide", "concepts", "timeseries"]
 type = "docs"
-[menu.docs]
 aliases = ["/docs/grafana/latest/guides/timeseries"]
+[menu.docs]
 name = "Time series"
 identifier = "time_series"
 parent = "guides"

docs/sources/menu.yaml

@@ -9,6 +9,8 @@
       link: /getting-started/timeseries/
     - name: Intro to histograms
       link: /getting-started/intro-histograms/
+    - name: Observability strategies
+      link: /getting-started/strategies/
     - name: Glossary
       link: /getting-started/glossary/
 - name: Installation