dont do logbias=throughput, fragmentation might not be worth it

bundles/postgresql/metadata.py

@@ -30,7 +30,6 @@ if node.has_bundle('zfs'):
                 'mountpoint': '/var/lib/postgresql',
                 'recordsize': '8192',
                 'atime': 'off',
-                'logbias': 'throughput',
             },
         },
     }

bundles/raspberry-pi/metadata.py

@@ -33,12 +33,6 @@ def zfs(metadata):
 
     return {
         'zfs': {
-            'datasets': {
-                name: {
-                    'logbias': 'throughput',
-                }
-                    for name in metadata.get('zfs/datasets')
-            },
             'kernel_params': {
                 'zfs_txg_timeout': 300,
             },