Merge pull request #99661 from dagiro/freshness134

freshness134

Author: TedA-M

articles/hdinsight/spark/apache-spark-improve-performance-iocache.md

@@ -6,7 +6,7 @@ ms.author: hrasheed
 ms.reviewer: jasonh
 ms.service: hdinsight
 ms.topic: conceptual
-ms.date: 10/29/2019
+ms.date: 12/23/2019
 ---
 
 # Improve performance of Apache Spark workloads using Azure HDInsight IO Cache
@@ -17,7 +17,7 @@ Most SSDs provide more than 1 GByte per second of bandwidth. This bandwidth, com
 
 > [!Note]  
 > IO Cache currently uses RubiX as a caching component, but this may change in future versions of the service. Please use IO Cache interfaces and don't take any dependencies directly on the RubiX implementation.
->IO Cache is only supported with Azure BLOB Storage at this time. 
+>IO Cache is only supported with Azure BLOB Storage at this time.
 
 ## Benefits of Azure HDInsight IO Cache
 
@@ -27,21 +27,19 @@ You don't have to make any changes to your Spark jobs to see performance increas
 
 ## Getting started
 
-Azure HDInsight IO Cache is deactivated by default in preview. IO Cache is available on Azure HDInsight 3.6+ Spark clusters, which run Apache Spark 2.3.  To activate IO Cache, do the following:
+Azure HDInsight IO Cache is deactivated by default in preview. IO Cache is available on Azure HDInsight 3.6+ Spark clusters, which run Apache Spark 2.3.  To activate IO Cache on HDInsight 4.0, do the following steps:
 
-1. Select your HDInsight cluster in [the Azure portal](https://portal.azure.com).
-
-1. In the **Overview** page (opened by default when you select the cluster) select **Ambari Home** under **Cluster dashboards**.
+1. From a web browser, navigate to `https://CLUSTERNAME.azurehdinsight.net`, where `CLUSTERNAME` is the name of your cluster.
 
 1. Select the **IO Cache** service on the left.
 
-1. Select **Actions** and **Activate**.
+1. Select **Actions** (**Service Actions** in HDI 3.6) and **Activate**.
 
     ![Enabling the IO Cache service in Ambari](./media/apache-spark-improve-performance-iocache/ambariui-enable-iocache.png "Enabling the IO Cache service in Ambari")
 
 1. Confirm restart of all the affected services on the cluster.
 
->[!NOTE]  
+> [!NOTE]  
 > Even though the progress bar shows activated, IO Cache isn't actually enabled until you restart the other affected services.
 
 ## Troubleshooting
@@ -66,12 +64,12 @@ You may get disk space errors running Spark jobs after enabling IO Cache. These
 
 1. Select **Restart** > **Restart All Affected**.
 
-    ![Apache Ambari restart all affected](./media/apache-spark-improve-performance-iocache/ambariui-restart-all-affected.png "Restart all affected")
+    ![Apache Ambari restarts all affected](./media/apache-spark-improve-performance-iocache/ambariui-restart-all-affected.png "Restart all affected")
 
 1. Select **Confirm Restart All**.
 
-If that does not work, disable IO Cache.
+If that doesn't work, disable IO Cache.
 
 ## Next Steps
 
-- Read more about IO Cache, including performance benchmarks in this blog post: [Apache Spark jobs gain up to 9x speed up with HDInsight IO Cache](https://azure.microsoft.com/blog/apache-spark-speedup-with-hdinsight-io-cache/)
+Read more about IO Cache, including performance benchmarks in this blog post: [Apache Spark jobs gain up to 9x speed up with HDInsight IO Cache](https://azure.microsoft.com/blog/apache-spark-speedup-with-hdinsight-io-cache/)