docs(zfs): First clean-up then Unmap/TRIM

README.md

@@ -168,6 +168,19 @@ zfs send --raw zpool/root/archlinux-frn@rekey | zstream dump | sed -n -e '/crypt
 
 Repeat for source dataset `zpool/root/archlinux-sxu@rekey`. You're particularly interested in parameters `DSL_CRYPTO_MASTER_KEY_1` and the initialization vector `DSL_CRYPTO_IV`. Notice that they differ between old and new dataset confirming that your new dataset has a new master key.
 
+### Clean-up
+
+Clean up:
+
+1. In newly keyed/reencrypted system dataset destroy its snapshot
+    ```
+    zfs destroy zpool/root/archlinux-frn@rekey
+    ```
+1. Recursively destroy source dataset
+    ```
+    zfs destroy -r zpool/root/archlinux-sxu
+    ```
+
 ### Unmap/TRIM
 
 Next up unmap/TRIM unallocated disk areas. If your zpool runs on an entire disk and not just on a partition, and if your disk supports TRIM you're going to want to do:
@@ -189,19 +202,6 @@ zpool status -t zpool
 zpool status zpool
 ```
 
-### Clean-up
-
-Optionally you may want to clean up:
-
-1. In newly keyed/reencrypted system dataset destroy its snapshot
-    ```
-    zfs destroy zpool/root/archlinux-frn@rekey
-    ```
-1. Recursively destroy source dataset
-    ```
-    zfs destroy -r zpool/root/archlinux-sxu
-    ```
-
 # ZFS setup explained
 
 The ZFS pool and dataset setup that makes this tick, explained in plain English.