diff --git a/fdbclient/StorageServerInterface.h b/fdbclient/StorageServerInterface.h
index bc340727fd..a3e421a128 100644
--- a/fdbclient/StorageServerInterface.h
+++ b/fdbclient/StorageServerInterface.h
@@ -451,7 +451,7 @@ struct ReadHotRangeWithMetrics {
 	ReadHotRangeWithMetrics(Arena& arena, const ReadHotRangeWithMetrics& rhs)
 	  : keys(arena, rhs.keys), density(rhs.density), readBandwidth(rhs.readBandwidth) {}
 
-	int expectedSize() { return keys.expectedSize() + sizeof(density) + sizeof(readBandwidth); }
+	int expectedSize() const { return keys.expectedSize() + sizeof(density) + sizeof(readBandwidth); }
 
 	template <class Ar>
 	void serialize(Ar& ar) {
diff --git a/fdbserver/KeyValueStoreMemory.actor.cpp b/fdbserver/KeyValueStoreMemory.actor.cpp
index fa2d47dbcd..2232fb27ac 100644
--- a/fdbserver/KeyValueStoreMemory.actor.cpp
+++ b/fdbserver/KeyValueStoreMemory.actor.cpp
@@ -279,7 +279,7 @@ private:
 		StringRef p1, p2;
 		OpRef() {}
 		OpRef(Arena& a, OpRef const& o) : op(o.op), p1(a, o.p1), p2(a, o.p2) {}
-		size_t expectedSize() { return p1.expectedSize() + p2.expectedSize(); }
+		size_t expectedSize() const { return p1.expectedSize() + p2.expectedSize(); }
 	};
 	struct OpHeader {
 		int op;