Merge pull request #110773 from rboucher/patch-3

Add note about pricing.

Author: PRMerger20

articles/azure-monitor/platform/metrics-custom-overview.md

@@ -1,15 +1,14 @@
 ---
-title: Custom metrics in Azure Monitor
+title: Custom metrics in Azure Monitor (preview)
 description: Learn about custom metrics in Azure Monitor and how they are modeled.
 author: ancav
 services: azure-monitor
-
 ms.topic: conceptual
-ms.date: 09/09/2019
+ms.date: 04/08/2020
 ms.author: ancav
 ms.subservice: metrics
 ---
-# Custom metrics in Azure Monitor
+# Custom metrics in Azure Monitor (preview)
 
 As you deploy resources and applications in Azure, you'll want to start collecting telemetry to gain insights into their performance and health. Azure makes some metrics available to you out of the box. These metrics are called standard or platform. However, they're limited in nature. You might want to collect some custom performance indicators or business-specific metrics to provide deeper insights.
 These **custom** metrics can be collected via your application telemetry, an agent that runs on your Azure resources, or even an outside-in monitoring system and submitted directly to Azure Monitor. After they're published to Azure Monitor, you can browse, query, and alert on custom metrics for your Azure resources and applications side by side with the standard metrics emitted by Azure.
@@ -19,7 +18,10 @@ Custom metrics can be sent to Azure Monitor via several methods:
 - Instrument your application by using the Azure Application Insights SDK and send custom telemetry to Azure Monitor. 
 - Install the Windows Azure Diagnostics (WAD) extension on your [Azure VM](collect-custom-metrics-guestos-resource-manager-vm.md), [virtual machine scale set](collect-custom-metrics-guestos-resource-manager-vmss.md), [classic VM](collect-custom-metrics-guestos-vm-classic.md), or [classic Cloud Services](collect-custom-metrics-guestos-vm-cloud-service-classic.md) and send performance counters to Azure Monitor. 
 - Install the [InfluxData Telegraf agent](collect-custom-metrics-linux-telegraf.md) on your Azure Linux VM and send metrics by using the Azure Monitor output plug-in.
-- Send custom metrics [directly to the Azure Monitor REST API](../../azure-monitor/platform/metrics-store-custom-rest-api.md), `https://<azureregion>.monitoring.azure.com/<AzureResourceID>/metrics`.
+- Send custom metrics [directly to the Azure Monitor REST API](../../azure-monitor/platform/metrics-store-custom-rest-api.md), `https://<azureregion>.monitoring.azure.com/<AzureResourceID>/metrics`. 
+
+> [!NOTE] 
+> Custom metrics are currently in public preview. After they are released for general availability (GA), using them will result in additional charges. For more information, see [Azure Monitor Pricing](https://azure.microsoft.com/pricing/details/monitor/). 
 
 When you send custom metrics to Azure Monitor, each data point, or value, reported must include the following information.
 
@@ -38,7 +40,6 @@ This property captures which Azure resource ID the custom metric is reported for
 > [!NOTE]  
 > You can't emit custom metrics against the resource ID of a resource group or subscription.
 >
->
 
 ### Region
 This property captures what Azure region the resource you're emitting metrics for is deployed in. Metrics must be emitted to the same Azure Monitor regional endpoint as the region the resource is deployed in. For example, custom metrics for a VM deployed in West US must be sent to the WestUS regional Azure Monitor endpoint. The region information is also encoded in the URL of the API call.
@@ -58,7 +59,7 @@ Namespaces are a way to categorize or group similar metrics together. By using n
 **Name** is the name of the metric that's being reported. Usually, the name is descriptive enough to help identify what's measured. An example is a metric that measures the number of memory bytes used on a given VM. It might have a metric name like **Memory Bytes In Use**.
 
 ### Dimension keys
-A dimension is a key or value pair that helps describe additional characteristics about the metric being collected. By using the additional characteristics, you can collect more information about the metric, which allows for deeper insights. For example, the **Memory Bytes In Use** metric might have a dimension key called **Process** that captures how many bytes of memory each process on a VM consumes. By using this key, you can filter the metric to see how much memory specific processes use or to identify the top five processes by memory usage.
+A dimension is a key or value pair that helps describe additional characteristics about the metric being collected. By using the additional characteristics, you can collect more information about the metric, which allows for deeper insights. For example, the **Memory Bytes In Use** metric might have a dimension key called **Process** that captures how many bytes of memory each process on a VM consumes. By using this key, you can filter the metric to see how much memory-specific processes use or to identify the top five processes by memory usage.
 Dimensions are optional, not all metrics may have dimensions. A custom metric can have up to 10 dimensions.
 
 ### Dimension values