presense -> presence

nexus/src/app/sagas/region_replacement_drive.rs

@@ -1368,7 +1368,7 @@ async fn srrd_drive_region_replacement_execute(
                     // If the Volume is active, that means reconcilation
                     // completed ok, and therefore Nexus can consider this
                     // repair complete. This is only true if one repair occurs
-                    // at a time per volume (which is true due to the presense
+                    // at a time per volume (which is true due to the presence
                     // of volume_repair records), and if this saga locks the
                     // region replacement request record as part of it executing
                     // (which it does through the SET_SAGA_ID forward action).

nexus/tests/integration_tests/volume_management.rs

@@ -356,7 +356,7 @@ async fn test_snapshot_prevents_other_disk(
     // The Crucible snapshots still remain
     assert!(!disk_test.crucible_resources_deleted().await);
 
-    // Attempt disk allocation, which will fail - the presense of the snapshot
+    // Attempt disk allocation, which will fail - the presence of the snapshot
     // means the region wasn't deleted.
     let disk_size = ByteCount::from_gibibytes_u32(10);
     let next_disk_name: Name = "next-disk".parse().unwrap();