diff --git a/CHANGES.txt b/CHANGES.txt
index 190994165a..4f714897a5 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -18,6 +18,7 @@
  * cqlsh: Fix handling of $$-escaped strings (CASSANDRA-12189)
  * Fix SSL JMX requiring truststore containing server cert (CASSANDRA-12109)
 Merged from 3.0:
+ * Faster startup by only scanning each directory for temporary files once (CASSANDRA-12114)
  * Respond with v1/v2 protocol header when responding to driver that attempts
    to connect with too low of a protocol version (CASSANDRA-11464)
  * NullPointerExpception when reading/compacting table (CASSANDRA-11988)
diff --git a/src/java/org/apache/cassandra/db/ColumnFamilyStore.java b/src/java/org/apache/cassandra/db/ColumnFamilyStore.java
index 938ea32525..a71b7520fc 100644
--- a/src/java/org/apache/cassandra/db/ColumnFamilyStore.java
+++ b/src/java/org/apache/cassandra/db/ColumnFamilyStore.java
@@ -610,6 +610,7 @@ public class ColumnFamilyStore implements ColumnFamilyStoreMBean
     public static void scrubDataDirectories(CFMetaData metadata) throws StartupException
     {
         Directories directories = new Directories(metadata, initialDirectories);
+        Set<File> cleanedDirectories = new HashSet<>();
 
          // clear ephemeral snapshots that were not properly cleared last session (CASSANDRA-7357)
         clearEphemeralSnapshots(directories);
@@ -628,10 +629,15 @@ public class ColumnFamilyStore implements ColumnFamilyStoreMBean
         for (Map.Entry<Descriptor,Set<Component>> sstableFiles : directories.sstableLister(Directories.OnTxnErr.IGNORE).list().entrySet())
         {
             Descriptor desc = sstableFiles.getKey();
+            File directory = desc.directory;
             Set<Component> components = sstableFiles.getValue();
 
-            for (File tmpFile : desc.getTemporaryFiles())
-                tmpFile.delete();
+            if (!cleanedDirectories.contains(directory))
+            {
+                cleanedDirectories.add(directory);
+                for (File tmpFile : desc.getTemporaryFiles())
+                    tmpFile.delete();
+            }
 
             File dataFile = new File(desc.filenameFor(Component.DATA));
             if (components.contains(Component.DATA) && dataFile.length() > 0)