diff --git a/bundles/mailserver/metadata.py b/bundles/mailserver/metadata.py
index af643d1..950e7dc 100644
--- a/bundles/mailserver/metadata.py
+++ b/bundles/mailserver/metadata.py
@@ -33,6 +33,7 @@ defaults = {
                 'mountpoint': '/var/vmail',
                 'compression': 'on',
                 'atime': 'off',
+                'recordsize': '16K',
             },
             'tank/vmail/index': {
                 'mountpoint': '/var/vmail/index',