diff --git a/src/infrastructure/storage/management/workflow/PhabricatorStorageManagementDumpWorkflow.php b/src/infrastructure/storage/management/workflow/PhabricatorStorageManagementDumpWorkflow.php
index 7195e735c6..4dc5c64042 100644
--- a/src/infrastructure/storage/management/workflow/PhabricatorStorageManagementDumpWorkflow.php
+++ b/src/infrastructure/storage/management/workflow/PhabricatorStorageManagementDumpWorkflow.php
@@ -1,213 +1,232 @@
 <?php
 
 final class PhabricatorStorageManagementDumpWorkflow
   extends PhabricatorStorageManagementWorkflow {
 
   protected function didConstruct() {
     $this
       ->setName('dump')
       ->setExamples('**dump** [__options__]')
       ->setSynopsis(pht('Dump all data in storage to stdout.'))
       ->setArguments(
         array(
           array(
             'name' => 'for-replica',
             'help' => pht(
               'Add __--master-data__ to the __mysqldump__ command, '.
               'generating a CHANGE MASTER statement in the output.'),
           ),
           array(
             'name' => 'output',
             'param' => 'file',
             'help' => pht(
               'Write output directly to disk. This handles errors better '.
               'than using pipes. Use with __--compress__ to gzip the '.
               'output.'),
           ),
           array(
             'name' => 'compress',
             'help' => pht(
               'With __--output__, write a compressed file to disk instead '.
               'of a plaintext file.'),
           ),
           array(
             'name' => 'overwrite',
             'help' => pht(
               'With __--output__, overwrite the output file if it already '.
               'exists.'),
           ),
         ));
   }
 
   protected function isReadOnlyWorkflow() {
     return true;
   }
 
   public function didExecute(PhutilArgumentParser $args) {
     $api = $this->getSingleAPI();
     $patches = $this->getPatches();
 
     $console = PhutilConsole::getConsole();
 
     $applied = $api->getAppliedPatches();
     if ($applied === null) {
       $namespace = $api->getNamespace();
       $console->writeErr(
         pht(
           '**Storage Not Initialized**: There is no database storage '.
           'initialized in this storage namespace ("%s"). Use '.
           '**%s** to initialize storage.',
           $namespace,
           './bin/storage upgrade'));
       return 1;
     }
 
     $databases = $api->getDatabaseList($patches, true);
 
     list($host, $port) = $this->getBareHostAndPort($api->getHost());
 
     $has_password = false;
 
     $password = $api->getPassword();
     if ($password) {
       if (strlen($password->openEnvelope())) {
         $has_password = true;
       }
     }
 
     $output_file = $args->getArg('output');
     $is_compress = $args->getArg('compress');
     $is_overwrite = $args->getArg('overwrite');
 
     if ($is_compress) {
       if ($output_file === null) {
         throw new PhutilArgumentUsageException(
           pht(
             'The "--compress" flag can only be used alongside "--output".'));
       }
     }
 
     if ($is_overwrite) {
       if ($output_file === null) {
         throw new PhutilArgumentUsageException(
           pht(
             'The "--overwrite" flag can only be used alongside "--output".'));
       }
     }
 
     if ($output_file !== null) {
       if (Filesystem::pathExists($output_file)) {
         if (!$is_overwrite) {
           throw new PhutilArgumentUsageException(
             pht(
               'Output file "%s" already exists. Use "--overwrite" '.
               'to overwrite.',
               $output_file));
         }
       }
     }
 
     $argv = array();
     $argv[] = '--hex-blob';
     $argv[] = '--single-transaction';
     $argv[] = '--default-character-set=utf8';
 
     if ($args->getArg('for-replica')) {
       $argv[] = '--master-data';
     }
 
     $argv[] = '-u';
     $argv[] = $api->getUser();
     $argv[] = '-h';
     $argv[] = $host;
 
     if ($port) {
       $argv[] = '--port';
       $argv[] = $port;
     }
 
     $argv[] = '--databases';
     foreach ($databases as $database) {
       $argv[] = $database;
     }
 
 
     if ($has_password) {
       $command = csprintf('mysqldump -p%P %Ls', $password, $argv);
     } else {
       $command = csprintf('mysqldump %Ls', $argv);
     }
 
+    // Decrease the CPU priority of this process so it doesn't contend with
+    // other more important things.
+    if (function_exists('proc_nice')) {
+      proc_nice(19);
+    }
+
+
     // If we aren't writing to a file, just passthru the command.
     if ($output_file === null) {
       return phutil_passthru('%C', $command);
     }
 
     // If we are writing to a file, stream the command output to disk. This
     // mode makes sure the whole command fails if there's an error (commonly,
     // a full disk). See T6996 for discussion.
 
     if ($is_compress) {
-      $file = gzopen($output_file, 'wb');
+      $file = gzopen($output_file, 'wb1');
     } else {
       $file = fopen($output_file, 'wb');
     }
 
     if (!$file) {
       throw new Exception(
         pht(
           'Failed to open file "%s" for writing.',
           $file));
     }
 
     $future = new ExecFuture('%C', $command);
 
-    $lines = new LinesOfALargeExecFuture($future);
-
     try {
-      foreach ($lines as $line) {
-        $line = $line."\n";
-        if ($is_compress) {
-          $ok = gzwrite($file, $line);
-        } else {
-          $ok = fwrite($file, $line);
+      $iterator = id(new FutureIterator(array($future)))
+        ->setUpdateInterval(0.100);
+      foreach ($iterator as $ready) {
+        list($stdout, $stderr) = $future->read();
+        $future->discardBuffers();
+
+        if (strlen($stderr)) {
+          fwrite(STDERR, $stderr);
         }
 
-        if ($ok !== strlen($line)) {
-          throw new Exception(
-            pht(
-              'Failed to write %d byte(s) to file "%s".',
-              new PhutilNumber(strlen($line)),
-              $output_file));
+        if (strlen($stdout)) {
+          if ($is_compress) {
+            $ok = gzwrite($file, $stdout);
+          } else {
+            $ok = fwrite($file, $stdout);
+          }
+
+          if ($ok !== strlen($stdout)) {
+            throw new Exception(
+              pht(
+                'Failed to write %d byte(s) to file "%s".',
+                new PhutilNumber(strlen($stdout)),
+                $output_file));
+          }
+        }
+
+        if ($ready !== null) {
+          $ready->resolvex();
         }
       }
 
       if ($is_compress) {
         $ok = gzclose($file);
       } else {
         $ok = fclose($file);
       }
 
       if ($ok !== true) {
         throw new Exception(
           pht(
             'Failed to close file "%s".',
             $output_file));
       }
     } catch (Exception $ex) {
       // If we might have written a partial file to disk, try to remove it so
       // we don't leave any confusing artifacts laying around.
 
       try {
         Filesystem::remove($output_file);
       } catch (Exception $ex) {
         // Ignore any errors we hit.
       }
 
       throw $ex;
     }
 
     return 0;
   }
 
 }