Add comment explaining why identity check is sufficient.

1 files changed, 5 insertions, 0 deletions

diff --git a/searchcore/src/vespa/searchcore/proton/server/feedhandler.cpp b/searchcore/src/vespa/searchcore/proton/server/feedhandler.cpp
index 897e58139c1..90b9bbc7f34 100644
--- a/searchcore/src/vespa/searchcore/proton/server/feedhandler.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/feedhandler.cpp
@@ -96,6 +96,11 @@ void FeedHandler::performPut(FeedToken token, PutOperation &op) {
         }
         return;
     }
+    /*
+     * Check if document type repos are equal. DocumentTypeRepoFactory::make
+     * returns the same document type repo if document type configs are equal,
+     * thus we can just perform a cheaper identity check here.
+     */
     if (_repo != op.getDocument()->getRepo()) {
         op.deserializeDocument(*_repo);
     }