diff --git a/python/sglang/srt/managers/schedule_batch.py b/python/sglang/srt/managers/schedule_batch.py
index 71d4ca5d888..19bd07b88da 100644
--- a/python/sglang/srt/managers/schedule_batch.py
+++ b/python/sglang/srt/managers/schedule_batch.py
@@ -694,6 +694,7 @@ def prepare_for_extend(self):
         #    (req.req_pool_idx, slice(pre_len, seq_len)),
         #    out_cache_loc[pt : pt + req.extend_input_len],
         # )
+        # TODO: some tensors can be reused for ForwardBatchInfo (e.g., extend_lens, cumsum_start)
 
         if self.model_config.is_encoder_decoder:
             self.prepare_encoder_info_extend(input_ids, seq_lens)
@@ -1146,6 +1147,7 @@ def write_req_to_token_pool_triton(
     pre_len = tl.load(pre_lens + pid)
     seq_len = tl.load(seq_lens + pid)
 
+    # TODO: optimize this?
     cumsum_start = 0
     for i in range(pid):
         cumsum_start += tl.load(extend_lens + i)
diff --git a/python/sglang/srt/model_executor/forward_batch_info.py b/python/sglang/srt/model_executor/forward_batch_info.py
index d839125448d..ea7c8d89a58 100644
--- a/python/sglang/srt/model_executor/forward_batch_info.py
+++ b/python/sglang/srt/model_executor/forward_batch_info.py
@@ -275,7 +275,7 @@ def compute_position_triton(
         extend_seq_lens_sum, dtype=torch.int64, device=extend_seq_lens.device
     )
     extend_start_loc = torch.empty(
-        batch_size, dtype=torch.int64, device=extend_seq_lens.device
+        batch_size, dtype=torch.int32, device=extend_seq_lens.device
     )
 
     # Launch kernel
@@ -302,6 +302,7 @@ def compute_position_kernel(
     prefix_len = tl.load(extend_prefix_lens + pid)
     seq_len = tl.load(extend_seq_lens + pid)
 
+    # TODO: optimize this?
     cumsum_start = 0
     for i in range(pid):
         cumsum_start += tl.load(extend_seq_lens + i)