diff --git a/core/lib/Drupal/Core/Cache/ChainedFastBackend.php b/core/lib/Drupal/Core/Cache/ChainedFastBackend.php
index 9f6be9d8ab..9b9ea3eb6c 100644
--- a/core/lib/Drupal/Core/Cache/ChainedFastBackend.php
+++ b/core/lib/Drupal/Core/Cache/ChainedFastBackend.php
@@ -301,7 +301,7 @@ protected function markAsOutdated() {
     // the same millisecond and are then incorrectly invalidated, but that only
     // costs one additional roundtrip to the persistent cache.
     $now = round(microtime(TRUE) + .001, 3);
-    if ($now > $this->getLastWriteTimestamp()) {
+    if ($now - 0.002 > $this->getLastWriteTimestamp()) {
       $this->lastWriteTimestamp = $now;
       $this->consistentBackend->set(self::LAST_WRITE_TIMESTAMP_PREFIX . $this->bin, $this->lastWriteTimestamp);
     }