diff --git a/exps/NATS-algos/search-size.py b/exps/NATS-algos/search-size.py
index c3c3dcc..d0a9931 100644
--- a/exps/NATS-algos/search-size.py
+++ b/exps/NATS-algos/search-size.py
@@ -2,7 +2,13 @@
 # Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2020 #
 ######################################################################################
 # In this file, we aims to evaluate three kinds of channel searching strategies:
-# - 
+# - channel-wise interpaltion from "Network Pruning via Transformable Architecture Search, NeurIPS 2019"
+# - masking + Gumbel-Softmax from "FBNetV2: Differentiable Neural Architecture Search for Spatial and Channel Dimensions, CVPR 2020"
+# - masking + sampling from "Can Weight Sharing Outperform Random Architecture Search? An Investigation With TuNAS, CVPR 2020"
+# For simplicity, we use tas, fbv2, and tunas to refer these three strategies. Their official implementations are at the following links:
+# - TAS: https://github.com/D-X-Y/AutoDL-Projects/blob/master/docs/NeurIPS-2019-TAS.md
+# - FBV2: https://github.com/facebookresearch/mobile-vision
+# - TuNAS: https://github.com/google-research/google-research/tree/master/tunas
 ####
 # python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo tunas --arch_weight_decay 0 --warmup_ratio 0.25
 ####
diff --git a/exps/experimental/vis-nats-bench-ws.py b/exps/experimental/vis-nats-bench-ws.py
index 563c9e6..b1d5014 100644
--- a/exps/experimental/vis-nats-bench-ws.py
+++ b/exps/experimental/vis-nats-bench-ws.py
@@ -26,7 +26,8 @@ from nats_bench import create
 from log_utils import time_string
 
 
-def fetch_data(root_dir='./output/search', search_space='tss', dataset=None, suffix='-AWD0.0-WARMNone'):
+# def fetch_data(root_dir='./output/search', search_space='tss', dataset=None, suffix='-WARMNone'):
+def fetch_data(root_dir='./output/search', search_space='tss', dataset=None, suffix='-WARM0.3'):
   ss_dir = '{:}-{:}'.format(root_dir, search_space)
   alg2name, alg2path = OrderedDict(), OrderedDict()
   seeds = [777, 888, 999]
@@ -39,9 +40,12 @@ def fetch_data(root_dir='./output/search', search_space='tss', dataset=None, suf
     alg2name['ENAS'] = 'enas-affine0_BN0-None'
     alg2name['SETN'] = 'setn-affine0_BN0-None'
   else:
-    alg2name['TAS'] = 'tas-affine0_BN0{:}'.format(suffix)
-    alg2name['FBNetV2'] = 'fbv2-affine0_BN0{:}'.format(suffix)
-    alg2name['TuNAS'] = 'tunas-affine0_BN0{:}'.format(suffix)
+    # alg2name['TAS'] = 'tas-affine0_BN0{:}'.format(suffix)
+    # alg2name['FBNetV2'] = 'fbv2-affine0_BN0{:}'.format(suffix)
+    # alg2name['TuNAS'] = 'tunas-affine0_BN0{:}'.format(suffix)
+    alg2name['channel-wise interpaltion'] = 'tas-affine0_BN0-AWD0.001{:}'.format(suffix)
+    alg2name['masking + Gumbel-Softmax'] = 'fbv2-affine0_BN0-AWD0.001{:}'.format(suffix)
+    alg2name['masking + sampling'] = 'tunas-affine0_BN0-AWD0.0{:}'.format(suffix)
   for alg, name in alg2name.items():
     alg2path[alg] = os.path.join(ss_dir, dataset, name, 'seed-{:}-last-info.pth')
   alg2data = OrderedDict()
@@ -98,8 +102,11 @@ def visualize_curve(api, vis_save_dir, search_space):
     for idx, (alg, data) in enumerate(alg2data.items()):
       print('plot alg : {:}'.format(alg))
       xs, accuracies = [], []
-      for iepoch in range(epochs+1):
-        structures, accs = [_[iepoch-1] for _ in data], []
+      for iepoch in range(epochs + 1):
+        try:
+          structures, accs = [_[iepoch-1] for _ in data], []
+        except:
+          raise ValueError('This alg {:} on {:} has invalid checkpoints.'.format(alg, dataset))
         for structure in structures:
           info = api.get_more_info(structure, dataset=dataset, hp=90 if api.search_space_name == 'size' else 200, is_random=False)
           accs.append(info['test-accuracy'])
@@ -131,5 +138,5 @@ if __name__ == '__main__':
 
   save_dir = Path(args.save_dir)
 
-  api = create(None, args.search_space, verbose=False)
+  api = create(None, args.search_space, fast_mode=True, verbose=False)
   visualize_curve(api, save_dir, args.search_space)
diff --git a/lib/models/shape_searchs/generic_size_tiny_cell_model.py b/lib/models/shape_searchs/generic_size_tiny_cell_model.py
index e1a00f9..e6e5ff3 100644
--- a/lib/models/shape_searchs/generic_size_tiny_cell_model.py
+++ b/lib/models/shape_searchs/generic_size_tiny_cell_model.py
@@ -2,8 +2,8 @@
 # Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2019.01 #
 #####################################################
 # Here, we utilized three techniques to search for the number of channels:
-# - feature interpaltion from "Network Pruning via Transformable Architecture Search, NeurIPS 2019"
-# - masking + GumbelSoftmax from "FBNetV2: Differentiable Neural Architecture Search for Spatial and Channel Dimensions, CVPR 2020"
+# - channel-wise interpaltion from "Network Pruning via Transformable Architecture Search, NeurIPS 2019"
+# - masking + Gumbel-Softmax from "FBNetV2: Differentiable Neural Architecture Search for Spatial and Channel Dimensions, CVPR 2020"
 # - masking + sampling from "Can Weight Sharing Outperform Random Architecture Search? An Investigation With TuNAS, CVPR 2020"
 from typing import List, Text, Any
 import random, torch
@@ -55,10 +55,10 @@ class GenericNAS301Model(nn.Module):
     assert algo in ['fbv2', 'tunas', 'tas'], 'invalid algo : {:}'.format(algo)
     self._algo = algo
     self._arch_parameters = nn.Parameter(1e-3*torch.randn(self._max_num_Cs, len(self._candidate_Cs)))
-    if algo == 'fbv2' or algo == 'tunas':
-      self.register_buffer('_masks', torch.zeros(len(self._candidate_Cs), max(self._candidate_Cs)))
-      for i in range(len(self._candidate_Cs)):
-        self._masks.data[i, :self._candidate_Cs[i]] = 1
+    # if algo == 'fbv2' or algo == 'tunas':
+    self.register_buffer('_masks', torch.zeros(len(self._candidate_Cs), max(self._candidate_Cs)))
+    for i in range(len(self._candidate_Cs)):
+      self._masks.data[i, :self._candidate_Cs[i]] = 1
   
   @property
   def tau(self):
diff --git a/lib/nats_bench/api_size.py b/lib/nats_bench/api_size.py
index 14cc5b5..d10425c 100644
--- a/lib/nats_bench/api_size.py
+++ b/lib/nats_bench/api_size.py
@@ -7,7 +7,6 @@
 # [2020.08.31] NATS-sss-v1_0-50262.pickle.pbz2                                      #
 #####################################################################################
 import os, copy, random, numpy as np
-from pathlib import Path
 from typing import List, Text, Union, Dict, Optional
 from collections import OrderedDict, defaultdict
 from .api_utils import time_string
@@ -15,6 +14,8 @@ from .api_utils import pickle_load
 from .api_utils import ArchResults
 from .api_utils import NASBenchMetaAPI
 from .api_utils import remap_dataset_set_names
+from .api_utils import nats_is_dir
+from .api_utils import nats_is_file
 from .api_utils import PICKLE_EXT
 
 
@@ -70,20 +71,20 @@ class NATSsize(NASBenchMetaAPI):
       else:
         file_path_or_dict = os.path.join(os.environ['TORCH_HOME'], '{:}.{:}'.format(ALL_BASE_NAMES[-1], PICKLE_EXT))
       print ('{:} Try to use the default NATS-Bench (size) path from fast_mode={:} and path={:}.'.format(time_string(), self._fast_mode, file_path_or_dict))
-    if isinstance(file_path_or_dict, str) or isinstance(file_path_or_dict, Path):
+    if isinstance(file_path_or_dict, str):
       file_path_or_dict = str(file_path_or_dict)
       if verbose:
         print('{:} Try to create the NATS-Bench (size) api from {:} with fast_mode={:}'.format(time_string(), file_path_or_dict, fast_mode))
-      if not os.path.isfile(file_path_or_dict) and not os.path.isdir(file_path_or_dict):
+      if not nats_is_file(file_path_or_dict) and not nats_is_dir(file_path_or_dict):
         raise ValueError('{:} is neither a file or a dir.'.format(file_path_or_dict))
-      self.filename = Path(file_path_or_dict).name
+      self.filename = os.path.basename(file_path_or_dict)
       if fast_mode:
-        if os.path.isfile(file_path_or_dict):
+        if nats_is_file(file_path_or_dict):
           raise ValueError('fast_mode={:} must feed the path for directory : {:}'.format(fast_mode, file_path_or_dict))
         else:
           self._archive_dir = file_path_or_dict
       else:
-        if os.path.isdir(file_path_or_dict):
+        if nats_is_dir(file_path_or_dict):
           raise ValueError('fast_mode={:} must feed the path for file : {:}'.format(fast_mode, file_path_or_dict))
         else:
           file_path_or_dict = pickle_load(file_path_or_dict)
diff --git a/lib/nats_bench/api_topology.py b/lib/nats_bench/api_topology.py
index c8659fc..9b0dccb 100644
--- a/lib/nats_bench/api_topology.py
+++ b/lib/nats_bench/api_topology.py
@@ -7,7 +7,6 @@
 # [2020.08.31] NATS-tss-v1_0-3ffb9.pickle.pbz2                                      #
 #####################################################################################
 import os, copy, random, numpy as np
-from pathlib import Path
 from typing import List, Text, Union, Dict, Optional
 from collections import OrderedDict, defaultdict
 import warnings
@@ -16,6 +15,8 @@ from .api_utils import pickle_load
 from .api_utils import ArchResults
 from .api_utils import NASBenchMetaAPI
 from .api_utils import remap_dataset_set_names
+from .api_utils import nats_is_dir
+from .api_utils import nats_is_file
 from .api_utils import PICKLE_EXT
 
 
@@ -67,20 +68,20 @@ class NATStopology(NASBenchMetaAPI):
       else:
         file_path_or_dict = os.path.join(os.environ['TORCH_HOME'], '{:}.{:}'.format(ALL_BASE_NAMES[-1], PICKLE_EXT))
       print ('{:} Try to use the default NATS-Bench (topology) path from {:}.'.format(time_string(), file_path_or_dict))
-    if isinstance(file_path_or_dict, str) or isinstance(file_path_or_dict, Path):
+    if isinstance(file_path_or_dict, str):
       file_path_or_dict = str(file_path_or_dict)
       if verbose:
         print('{:} Try to create the NATS-Bench (topology) api from {:} with fast_mode={:}'.format(time_string(), file_path_or_dict, fast_mode))
-      if not os.path.isfile(file_path_or_dict) and not os.path.isdir(file_path_or_dict):
+      if not nats_is_file(file_path_or_dict) and not nats_is_dir(file_path_or_dict):
         raise ValueError('{:} is neither a file or a dir.'.format(file_path_or_dict))
-      self.filename = Path(file_path_or_dict).name
+      self.filename = os.path.basename(file_path_or_dict)
       if fast_mode:
-        if os.path.isfile(file_path_or_dict):
+        if nats_is_file(file_path_or_dict):
           raise ValueError('fast_mode={:} must feed the path for directory : {:}'.format(fast_mode, file_path_or_dict))
         else:
           self._archive_dir = file_path_or_dict
       else:
-        if os.path.isdir(file_path_or_dict):
+        if nats_is_dir(file_path_or_dict):
           raise ValueError('fast_mode={:} must feed the path for file : {:}'.format(fast_mode, file_path_or_dict))
         else:
           file_path_or_dict = pickle_load(file_path_or_dict)
diff --git a/lib/nats_bench/api_utils.py b/lib/nats_bench/api_utils.py
index 4f7ca35..aa49969 100644
--- a/lib/nats_bench/api_utils.py
+++ b/lib/nats_bench/api_utils.py
@@ -17,6 +17,7 @@ from typing import List, Text, Union, Dict, Optional
 from collections import OrderedDict, defaultdict
 
 
+_FILE_SYSTEM = 'default'
 PICKLE_EXT = 'pickle.pbz2'
 
 
@@ -45,6 +46,34 @@ def time_string():
   return string
 
 
+def reset_file_system(lib: Text='default'):
+  _FILE_SYSTEM = lib
+
+
+def get_file_system(lib: Text='default'):
+  return _FILE_SYSTEM
+
+
+def nats_is_dir(file_path):
+  if _FILE_SYSTEM == 'default':
+    return os.path.isdir(file_path)
+  elif _FILE_SYSTEM == 'google':
+    import tensorflow as tf
+    return tf.gfile.isdir(file_path)
+  else:
+    raise ValueError('Unknown file system lib: {:}'.format(_FILE_SYSTEM))
+
+
+def nats_is_file(file_path):
+  if _FILE_SYSTEM == 'default':
+    return os.path.isfile(file_path)
+  elif _FILE_SYSTEM == 'google':
+    import tensorflow as tf
+    return tf.gfile.exists(file_path) and not tf.gfile.isdir(file_path)
+  else:
+    raise ValueError('Unknown file system lib: {:}'.format(_FILE_SYSTEM))
+
+
 def remap_dataset_set_names(dataset, metric_on_set, verbose=False):
   """re-map the metric_on_set to internal keys"""
   if verbose:
@@ -146,10 +175,10 @@ class NASBenchMetaAPI(metaclass=abc.ABCMeta):
             time_string(), archive_root, index))
     if archive_root is None:
       archive_root = os.path.join(os.environ['TORCH_HOME'], '{:}-full'.format(self.ALL_BASE_NAMES[-1]))
-      if not os.path.isdir(archive_root):
+      if not nats_is_dir(archive_root):
         warnings.warn('The input archive_root is None and the default archive_root path ({:}) does not exist, try to use self.archive_dir.'.format(archive_root))
         archive_root = self.archive_dir
-    if archive_root is None or not os.path.isdir(archive_root):
+    if archive_root is None or not nats_is_dir(archive_root):
       raise ValueError('Invalid archive_root : {:}'.format(archive_root))
     if index is None:
       indexes = list(range(len(self)))
@@ -158,9 +187,9 @@ class NASBenchMetaAPI(metaclass=abc.ABCMeta):
     for idx in indexes:
       assert 0 <= idx < len(self.meta_archs), 'invalid index of {:}'.format(idx)
       xfile_path = os.path.join(archive_root, '{:06d}.{:}'.format(idx, PICKLE_EXT))
-      if not os.path.isfile(xfile_path):
+      if not nats_is_file(xfile_path):
         xfile_path = os.path.join(archive_root, '{:d}.{:}'.format(idx, PICKLE_EXT))
-      assert os.path.isfile(xfile_path), 'invalid data path : {:}'.format(xfile_path)
+      assert nats_is_file(xfile_path), 'invalid data path : {:}'.format(xfile_path)
       xdata = pickle_load(xfile_path)
       assert isinstance(xdata, dict), 'invalid format of data in {:}'.format(xfile_path)
       self.evaluated_indexes.add(idx)
diff --git a/scripts-search/NATS/search-size.sh b/scripts-search/NATS/search-size.sh
index 61c64c7..df5b97d 100644
--- a/scripts-search/NATS/search-size.sh
+++ b/scripts-search/NATS/search-size.sh
@@ -1,10 +1,10 @@
 #!/bin/bash
-# bash ./NATS/search-size.sh 0 777
+# bash scripts-search/NATS/search-size.sh 0 0.3 777
 echo script name: $0
 echo $# arguments
-if [ "$#" -ne 2 ] ;then
+if [ "$#" -ne 3 ] ;then
   echo "Input illegal number of parameters " $#
-  echo "Need 2 parameters for GPU-device and seed"
+  echo "Need 3 parameters for GPU-device, warmup-ratio, and seed"
   exit 1
 fi
 if [ "$TORCH_HOME" = "" ]; then
@@ -15,16 +15,19 @@ else
 fi
 
 device=$1
-seed=$2
+ratio=$2
+seed=$3
 
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo tas --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo tas --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo tas --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo tas --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo tas --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo tas --warmup_ratio ${ratio} --rand_seed ${seed}
 
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo fbv2 --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo fbv2 --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo fbv2 --rand_seed ${seed}
+#
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo fbv2 --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo fbv2 --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo fbv2 --warmup_ratio ${ratio} --rand_seed ${seed}
 
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo tunas --arch_weight_decay 0 --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo tunas --arch_weight_decay 0 --rand_seed ${seed}
-CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo tunas --arch_weight_decay 0 --rand_seed ${seed}
+#
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar10  --data_path $TORCH_HOME/cifar.python --algo tunas --arch_weight_decay 0 --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset cifar100 --data_path $TORCH_HOME/cifar.python --algo tunas --arch_weight_decay 0 --warmup_ratio ${ratio} --rand_seed ${seed}
+CUDA_VISIBLE_DEVICES=${device} python ./exps/NATS-algos/search-size.py --dataset ImageNet16-120 --data_path $TORCH_HOME/cifar.python/ImageNet16 --algo tunas --arch_weight_decay 0 --warmup_ratio ${ratio} --rand_seed ${seed}