Merge pull request #111200 from lgayhardt/appinsightsdaleprice0420

 App Insights Pricing Update from Dale

Author: PRMerger12

articles/azure-monitor/app/pricing.md

@@ -24,6 +24,8 @@ The pricing for [Azure Application Insights][start] is a **Pay-As-You-Go** model
 
 [Multi-step web tests](../../azure-monitor/app/availability-multistep.md) incur an additional charge. Multi-step web tests are web tests that perform a sequence of actions. There's no separate charge for *ping tests* of a single page. Telemetry from ping tests and multi-step tests is charged the same as other telemetry from your app.
 
+The Application Insights option to [Enable alerting on custom metric dimensions](https://docs.microsoft.com/azure/azure-monitor/app/pre-aggregated-metrics-log-metrics#custom-metrics-dimensions-and-pre-aggregation) can also generate in additional costs because this can result in the creation of additional pre-aggregation metrics. [Learn more] about log-based and pre-aggregated metrics in Application Insights and about [pricing](https://azure.microsoft.com/pricing/details/monitor/) for Azure Monitor custom metrics.
+
 ## Estimating the costs to manage your application
 
 If you're not yet using Application Insights, you can use the [Azure Monitor pricing calculator](https://azure.microsoft.com/pricing/calculator/?service=monitor) to estimate the cost of using Application Insights. Start by entering "Azure Monitor" in the Search box, and clicking on the resulting Azure Monitor tile. Scroll down the page to Azure Monitor, and select Application Insights from the Type dropdown.  Here you can enter the number of GB of data you expect to collect per month, so the question is how much data will Application Insights collect monitoring your application.
@@ -172,7 +174,7 @@ To [change the daily cap via Azure Resource Manager](../../azure-monitor/app/pow
 
 ### Create alerts for the Daily Cap
 
-The Application Insights Daily Cap creates an event in the Azure activity kog when the ingested data volumes hits the warning level or the daily cap level.  You can [create an alert based on these activity log events](https://docs.microsoft.com/azure/azure-monitor/platform/alerts-activity-log#create-with-the-azure-portal). The signal names for these events are:
+The Application Insights Daily Cap creates an event in the Azure activity log when the ingested data volumes hits the warning level or the daily cap level.  You can [create an alert based on these activity log events](https://docs.microsoft.com/azure/azure-monitor/platform/alerts-activity-log#create-with-the-azure-portal). The signal names for these events are:
 
 * Application Insights component daily cap warning threshold reached
 
@@ -212,7 +214,7 @@ To change the retention, from your Application Insights resource, go to the **Us
 
 ![Adjust the daily telemetry volume cap](./media/pricing/pricing-005.png)
 
-The retention can also be [set programatically using PowerShell](powershell.md#set-the-data-retention) using the `retentionInDays` parameter. Additionally, if you set the data retention to 30 days, you can trigger an immediate purge of older data using the `immediatePurgeDataOn30Days` parameter, which may be useful for compliance-related scenarios. This purge functionality is only exposed via Azure Resource Manager and should be used with extreme care. The daily reset time for the data volume cap can be configured using Azure Resource Manager to set the `dailyQuotaResetTime` parameter.
+The retention can also be [set programatically using PowerShell](powershell.md#set-the-data-retention) using the `retentionInDays` parameter. When the retention is lowered, there is a several day grace period before the oldest data is removed. If you set the data retention to 30 days, you can trigger an immediate purge of older data using the `immediatePurgeDataOn30Days` parameter, which may be useful for compliance-related scenarios. This purge functionality is only exposed via Azure Resource Manager and should be used with extreme care. The daily reset time for the data volume cap can be configured using Azure Resource Manager to set the `dailyQuotaResetTime` parameter.
 
 ## Data transfer charges using Application Insights
 
@@ -224,7 +226,7 @@ Sending data to Application Insights might incur data bandwidth charges. As desc
 
 ## Disable daily cap e-mails
 
-To disable the daily volume cap e-mails, under the **Configure** section of your Application Insights resource, in the **Usage and estimated costs** pane, select  **Daily Cap**. There are settings to send e-mail when the cap is reached, as well as when an adjustable warning level has been reached. If you wish to disable all daily cap volume-related emails uncheck both boxes.
+To disable the daily volume cap e-mails, under the **Configure** section of your Application Insights resource, in the **Usage and estimated costs** pane, select  **Daily Cap**. There are settings to send e-mail when the cap is reached, as well as when an adjustable warning level has been reached. If you wish to disable all daily cap volume-related emails, uncheck both boxes.
 
 ## Legacy Enterprise (Per Node) pricing tier
 
@@ -291,4 +293,4 @@ You can write a script to set the pricing tier by using Azure Resource Managemen
 [apiproperties]: app-insights-api-custom-events-metrics.md#properties
 [start]: ../../azure-monitor/app/app-insights-overview.md
 [pricing]: https://azure.microsoft.com/pricing/details/application-insights/
-[pricing]: https://azure.microsoft.com/pricing/details/application-insights/
+[pricing]: https://azure.microsoft.com/pricing/details/application-insights/