diff --git a/khaosz/trainer/data_util.py b/khaosz/trainer/data_util.py
index bd9449d..9d6eb34 100644
--- a/khaosz/trainer/data_util.py
+++ b/khaosz/trainer/data_util.py
@@ -295,7 +295,8 @@ class RandomSampler(Sampler[int]):
         if self._indices is None:
             self._generate_indices()
         
-        for i in range(self.current_iter, n):
+        start = self.current_iter % n
+        for i in range(start, n):
             yield self._indices[i]
             self.current_iter += 1
         
@@ -303,8 +304,7 @@ class RandomSampler(Sampler[int]):
         self._indices = None
     
     def __len__(self):
-        n = len(self.data_source)
-        return n - self.current_iter % n
+        return len(self.data_source)
     
     def state_dict(self):
         return {
diff --git a/khaosz/trainer/trainer.py b/khaosz/trainer/trainer.py
index 2350195..4e182d0 100644
--- a/khaosz/trainer/trainer.py
+++ b/khaosz/trainer/trainer.py
@@ -37,8 +37,6 @@ class Trainer:
         ]
 
     def _set_train_kwargs(self, kwargs: dict):
-        used_epochs = 0
-        used_iters = 0
         seed = self.train_config.random_seed
         sampler = RandomSampler(data_source=self.train_config.dataset, seed=seed)
         optim = self.train_config.optimizer
@@ -59,8 +57,6 @@ class Trainer:
         
         if sampler_state: 
             sampler.load_state_dict(sampler_state)
-            used_epochs = sampler_state.get('epoch', 0)
-            used_iters = sampler_state.get('iter', 0)
         
         if optim_state: 
             optim.load_state_dict(optim_state)
@@ -76,8 +72,8 @@ class Trainer:
         
         kwargs["dataloader"] = dataloader
         kwargs["optimizer"] = self.train_config.optimizer
-        kwargs["epoch"] = used_epochs
-        kwargs["current_iter"] = used_iters
+        kwargs["epoch"] = sampler.epoch
+        kwargs["current_iter"] = sampler.current_iter
         kwargs["sampler"] = sampler
         kwargs["checkpoint"] = checkpoint
         
diff --git a/khaosz/trainer/trainer_callback.py b/khaosz/trainer/trainer_callback.py
index 59b2823..de898fc 100644
--- a/khaosz/trainer/trainer_callback.py
+++ b/khaosz/trainer/trainer_callback.py
@@ -103,9 +103,6 @@ class CheckpointCallback(TrainerCallback):
         checkpoint.sampler_state = random_sampler.state_dict()
         checkpoint.optim_state = optimizer.state_dict()
         
-        checkpoint.sampler_state['epoch'] = kwargs.get('epoch', 0)
-        checkpoint.sampler_state['current_iter'] = kwargs.get('current_iter', 0)
-        
         checkpoint.save(save_path)
     
     def on_batch_end(self, trainer: 'Trainer', **kwargs):