diff --git a/pg_backrest_backup.pm b/pg_backrest_backup.pm
index b0e64f379..8e4bf6a06 100644
--- a/pg_backrest_backup.pm
+++ b/pg_backrest_backup.pm
@@ -42,8 +42,7 @@ my $bArchiveRequired;
 # Thread variables
 my @oThread;
 my @oThreadQueue;
-my @oThreadFile;
-my $oMasterQueue;
+my @oMasterQueue;
 my %oFileCopyMap;
 
 ####################################################################################################################################
@@ -59,11 +58,6 @@ sub backup_init
     my $iThreadMaxParam = shift;
     my $bArchiveRequiredParam = shift;
 
-#    for (my $iFileIdx = 0; $iFileIdx < scalar @oFile; $iFileIdx++)
-#    {
-#        undef($oFile[$iFileIdx]);
-#    }
-
     $oDb = $oDbParam;
     $oFile = $oFileParam;
     $strType = $strTypeParam;
@@ -71,12 +65,12 @@ sub backup_init
     $bNoChecksum = $bNoChecksumParam;
     $iThreadMax = $iThreadMaxParam;
     $bArchiveRequired = $bArchiveRequiredParam;
-    
+
     if (!defined($iThreadMax))
     {
         $iThreadMax = 1;
     }
-    
+
     if ($iThreadMax < 1 || $iThreadMax > 32)
     {
         confess &log(ERROR, "thread_max must be between 1 and 32");
@@ -109,15 +103,9 @@ sub thread_init
     for (my $iThreadIdx = 0; $iThreadIdx < $iThreadActualTotal; $iThreadIdx++)
     {
         $oThreadQueue[$iThreadIdx] = Thread::Queue->new();
-
-#        if (!defined($oFile[$iThreadIdx + 1]))
-#        {
-#            $oFileThread[$iThreadIdx] = $oFile->clone($iThreadIdx + 1);
-#        }
+        $oMasterQueue[$iThreadIdx] = Thread::Queue->new();
     }
     
-    $oMasterQueue = Thread::Queue->new();
-    
     return $iThreadActualTotal;
 }
 
@@ -1037,47 +1025,50 @@ sub backup_file
     # Read the messages that we passed back from the threads.  These should be two types:
     # 1) remove - files that were skipped because they were removed from the database during backup
     # 2) checksum - file checksums calculated by the threads
-    while (my $strMessage = $oMasterQueue->dequeue_nb())
+    for (my $iThreadIdx = 0; $iThreadIdx < $iThreadLocalMax; $iThreadIdx++)
     {
-        &log (DEBUG, "message received in master queue: ${strMessage}");
-
-        # Split the message.  Currently using | as the split character.  Not ideal, but it will do for now.
-        my @strSplit = split(/\|/, $strMessage);
-
-        my $strCommand = $strSplit[0];      # Command to execute on a file
-        my $strFileSection = $strSplit[1];  # File section where the file is located
-        my $strFile = $strSplit[2];         # The file to act on
-
-        # These three parts are required
-        if (!defined($strCommand) || !defined($strFileSection) || !defined($strFile))
+        while (my $strMessage = $oMasterQueue[$iThreadIdx]->dequeue_nb())
         {
-            confess &log(ASSERT, "thread messages must have strCommand, strFileSection and strFile defined");
-        }
+            &log (DEBUG, "message received in master queue: ${strMessage}");
 
-        &log (DEBUG, "command = ${strCommand}, file_section = ${strFileSection}, file = ${strFile}");
+            # Split the message.  Currently using | as the split character.  Not ideal, but it will do for now.
+            my @strSplit = split(/\|/, $strMessage);
 
-        # If command is "remove" then mark the skipped file in the manifest
-        if ($strCommand eq "remove")
-        {
-            delete ${$oBackupManifestRef}{"${strFileSection}"}{"$strFile"};
+            my $strCommand = $strSplit[0];      # Command to execute on a file
+            my $strFileSection = $strSplit[1];  # File section where the file is located
+            my $strFile = $strSplit[2];         # The file to act on
 
-            &log (INFO, "marked skipped ${strFileSection}:${strFile} from the manifest");
-        }
-        # If command is "checksum" then record the checksum in the manifest
-        elsif ($strCommand eq "checksum")
-        {
-            my $strChecksum = $strSplit[3];  # File checksum calculated by the thread
-
-            # Checksum must be defined
-            if (!defined($strChecksum))
+            # These three parts are required
+            if (!defined($strCommand) || !defined($strFileSection) || !defined($strFile))
             {
-                confess &log(ASSERT, "thread checksum messages must have strChecksum defined");
+                confess &log(ASSERT, "thread messages must have strCommand, strFileSection and strFile defined");
             }
 
-            ${$oBackupManifestRef}{"${strFileSection}"}{"$strFile"}{checksum} = $strChecksum;
+            &log (DEBUG, "command = ${strCommand}, file_section = ${strFileSection}, file = ${strFile}");
 
-            # Log the checksum
-            &log (DEBUG, "write checksum ${strFileSection}:${strFile} into manifest: ${strChecksum}");
+            # If command is "remove" then mark the skipped file in the manifest
+            if ($strCommand eq "remove")
+            {
+                delete ${$oBackupManifestRef}{"${strFileSection}"}{"$strFile"};
+
+                &log (INFO, "marked skipped ${strFileSection}:${strFile} from the manifest");
+            }
+            # If command is "checksum" then record the checksum in the manifest
+            elsif ($strCommand eq "checksum")
+            {
+                my $strChecksum = $strSplit[3];  # File checksum calculated by the thread
+
+                # Checksum must be defined
+                if (!defined($strChecksum))
+                {
+                    confess &log(ASSERT, "thread checksum messages must have strChecksum defined");
+                }
+
+                ${$oBackupManifestRef}{"${strFileSection}"}{"$strFile"}{checksum} = $strChecksum;
+
+                # Log the checksum
+                &log (DEBUG, "write checksum ${strFileSection}:${strFile} into manifest: ${strChecksum}");
+            }
         }
     }
 }
@@ -1115,6 +1106,8 @@ sub backup_file_thread
                                               undef, $oFileCopyMap{$strFile}{modification_time},
                                               undef, $bPathCreate, false))
         {
+            &log(DEBUG, "thread ${iThreadIdx} unable to copy file: " . $oFileCopyMap{$strFile}{db_file});
+
             # If the copy fails then see if the file still exists on the database
             if (!$oFileThread->file_exists(PATH_DB_ABSOLUTE, $oFileCopyMap{$strFile}{db_file}))
             {
@@ -1127,7 +1120,7 @@ sub backup_file_thread
             }
 
             # Write a message into the master queue to have the file removed from the manifest
-            $oMasterQueue->enqueue("remove|$oFileCopyMap{$strFile}{file_section}|$oFileCopyMap{$strFile}{file}");
+            $oMasterQueue[$iThreadIdx]->enqueue("remove|$oFileCopyMap{$strFile}{file_section}|$oFileCopyMap{$strFile}{file}");
 
             # Move on to the next file
             next;
@@ -1140,7 +1133,7 @@ sub backup_file_thread
             my $strChecksum = $oFileThread->file_hash_get(PATH_BACKUP_TMP, $oFileCopyMap{$strFile}{backup_file});
 
             # Write the checksum message into the master queue
-            $oMasterQueue->enqueue("checksum|$oFileCopyMap{$strFile}{file_section}|$oFileCopyMap{$strFile}{file}|${strChecksum}");
+            $oMasterQueue[$iThreadIdx]->enqueue("checksum|$oFileCopyMap{$strFile}{file_section}|$oFileCopyMap{$strFile}{file}|${strChecksum}");
             
             &log(INFO, $strLog . " checksum ${strChecksum}");
         }