Merge pull request #15920 from ManikaDhiman/md-refs-updates

Updates to the ReFS dedup article

Author: prmerger-automator[bot]

azure-stack/hci/manage/refs-deduplication-and-compression.md

@@ -4,7 +4,7 @@ description: Learn how to use ReFS deduplication and compression in Azure Stack
 author: alkohli
 ms.author: alkohli
 ms.topic: how-to
-ms.date: 04/10/2024
+ms.date: 09/24/2024
 ---
 
 # Optimize storage with ReFS deduplication and compression in Azure Stack HCI
@@ -148,25 +148,24 @@ After you enable this feature, you can run a one-time job manually or schedule r
 
 Before you run, you should also factor these other considerations:
 
-- The first run after enabling this feature is always a full scan and optimization of the entire volume. If the `FullRun` parameter is specified, the optimization covers the entire volume rather than new or unoptimized data.
 - If you don't specify a compression format, the default algorithm is LZ4. You can change the algorithm from one run to another as needed.
 - You can specify more parameters for more complex use cases. The cmdlet used in this section is for the simplest use case.
-- The Full Run, Excluded folder, Excluded file extensions, and Minimum last modified time hours filters apply only when running deduplication, and don't apply when running compression.
+- The Excluded folder, Excluded file extensions, and Minimum last modified time hours filters apply only when running deduplication, and don't apply when running compression.
 
 **Manually run ReFS deduplication and compression jobs**
 
 - To start a job immediately, run the following cmdlet. Once you start a job, its `State` might appear as `NotStarted` because it could still be in the initialization phase.
 
     ```powershell
-    Start-ReFSDedupJob -Volume <path> -Duration <TimeSpan> -FullRun -CompressionFormat <LZ4 | ZSTD> 
+    Start-ReFSDedupJob -Volume <path> -Duration <TimeSpan> -CompressionFormat <LZ4 | ZSTD> 
     ```
 
     For example, the following cmdlet starts a job immediately for a duration of 5 hours using the LZ4 compression format:
 
     ```powershell
     PS C:\Users\hciuser> $Start = “10/31/2023 08:30:00”
     PS C:\Users\hciuser> $Duration = New-Timespan -Hours 5
-    PS C:\Users\hciuser> Start-ReFSDedupJob -Volume "C:\ClusterStorage\Volume1" -FullRun -Duration $Duration -CompressionFormat LZ4
+    PS C:\Users\hciuser> Start-ReFSDedupJob -Volume "C:\ClusterStorage\Volume1" -Duration $Duration -CompressionFormat LZ4
     
     Id     Name            PSJobTypeName   State         HasMoreData     Location             Command
     --     ----            -------------   -----         -----------     --------             -------
@@ -394,6 +393,32 @@ The duration limit is in place to prevent any performance impact on customer wor
 
 The following section lists the known issues that currently exist with ReFS deduplication and compression.
 
+### When Compression is enabled, using the `-FullRun` parameter on jobs after the first optimization run might result in a deadlock in the system.
+
+**Status:** Open.
+
+Avoid using `-FullRun` in manually started jobs unless the `Type` is `Dedup`.
+
+Follow these steps as a temporary workaround to mitigate this issue:
+
+1. Disable ReFS deduplication and compression on the volume:
+
+    ```powershell
+    Disable-ReFSDedup -Volume <path>
+    ```
+
+1. Decompress the volume using `refsutil`:
+
+    ```powershell
+    refsutil compression /c /f NONE <vol>
+    ```
+  
+1. Re-enable ReFS deduplication and compression with the `Dedup` only mode, if needed:
+
+    ```powershell
+    Enable-ReFSDedup -Volume <path> -Type Dedup
+    ```
+
 ### Scheduling jobs to run simultaneously on multiple CSVs within a single cluster can potentially trigger CSV movements and negatively impact performance.
 
 **Status:** Open.