diff --git a/src/blackmisc/datacache.cpp b/src/blackmisc/datacache.cpp
index c55033e28..ab523e301 100644
--- a/src/blackmisc/datacache.cpp
+++ b/src/blackmisc/datacache.cpp
@@ -243,7 +243,7 @@ namespace BlackMisc
         if (! lock) { return; }
         m_cache->m_revision.writeNewRevision(baseline.toTimestampMap());
 
-        auto msg = m_cache->saveToFiles(persistentStore(), values, baseline.toTimestampMapString());
+        auto msg = m_cache->saveToFiles(persistentStore(), values, baseline.toTimestampMapString(values.keys()));
         msg.setCategories(this);
         CLogMessage::preformatted(msg);
 
diff --git a/src/blackmisc/valuecache.cpp b/src/blackmisc/valuecache.cpp
index 4456437b9..bb5c505c6 100644
--- a/src/blackmisc/valuecache.cpp
+++ b/src/blackmisc/valuecache.cpp
@@ -91,13 +91,13 @@ namespace BlackMisc
         return result;
     }
 
-    QString CValueCachePacket::toTimestampMapString() const
+    QString CValueCachePacket::toTimestampMapString(const QStringList &keys) const
     {
-        auto map = toTimestampMap();
         QStringList result;
-        for (auto it = map.cbegin(); it != map.cend(); ++it)
+        for (const auto &key : keys)
         {
-            result.push_back(it.key() + "(" + QDateTime::fromMSecsSinceEpoch(it.value(), Qt::UTC).toString(Qt::ISODate) + ")");
+            QString time = contains(key) ? QDateTime::fromMSecsSinceEpoch(value(key).second, Qt::UTC).toString(Qt::ISODate) : "no timestamp";
+            result.push_back(key + "(" + time + ")");
         }
         return result.join(",");
     }
diff --git a/src/blackmisc/valuecache.h b/src/blackmisc/valuecache.h
index 9383417e7..c62aed5f9 100644
--- a/src/blackmisc/valuecache.h
+++ b/src/blackmisc/valuecache.h
@@ -94,7 +94,7 @@ namespace BlackMisc
         QMap<QString, qint64> toTimestampMap() const;
 
         //! Return map of timestamps converted to string.
-        QString toTimestampMapString() const;
+        QString toTimestampMapString(const QStringList &keys) const;
 
         //! Remove value matching the given key, and return it in a separate packet.
         CValueCachePacket takeByKey(const QString &key);