diff --git a/Database/ContentIdentifier.hs b/Database/ContentIdentifier.hs
index d40bf4faf5..bbf67dcfb1 100644
--- a/Database/ContentIdentifier.hs
+++ b/Database/ContentIdentifier.hs
@@ -77,7 +77,7 @@ databaseIsEmpty (ContentIdentifierHandle _ b) = b
 -- ContentIndentifiersKeyRemoteCidIndex speeds up queries like 
 -- getContentIdentifiers, but it is not used for
 -- getContentIdentifierKeys. ContentIndentifiersCidRemoteKeyIndex was
--- added to speed that up.
+-- addedto speed that up.
 share [mkPersist sqlSettings, mkMigrate "migrateContentIdentifier"] [persistLowerCase|
 ContentIdentifiers
   remote UUID
diff --git a/doc/todo/track_free_space_in_repos_via_git-annex_branch.mdwn b/doc/todo/track_free_space_in_repos_via_git-annex_branch.mdwn
index a50c698eb0..3b0acecbcc 100644
--- a/doc/todo/track_free_space_in_repos_via_git-annex_branch.mdwn
+++ b/doc/todo/track_free_space_in_repos_via_git-annex_branch.mdwn
@@ -78,3 +78,11 @@ Note that the use of `git cat-file` in union merge is not --buffer
 streaming, so is slower than the patch parsing method that was discussed in
 the previous section. So it might be possible to speed up git-annex branch
 merging using patch parsing.
+
+Note that Database.ContentIdentifier and Database.ImportFeed also update
+by diffing from the old to new git-annex branch (with `git cat-file` to
+read log files) so could also be sped up by being done at git-annex branch
+merge time. Those are less expensive than diffing the location logs only
+because the logs they diff are less often used, and the work is only 
+done when relevant commands are run.
+