diff --git a/python/tvm/relax/backend/dispatch_sort_scan.py b/python/tvm/relax/backend/dispatch_sort_scan.py
index 870e6138d7bd..e25c28e5711a 100644
--- a/python/tvm/relax/backend/dispatch_sort_scan.py
+++ b/python/tvm/relax/backend/dispatch_sort_scan.py
@@ -227,13 +227,13 @@ def estimate_thrust_workspace_size(self, call: relax.Call) -> int:
         int32_byte_per_elem = DataType("int32").bits // 8
         num_elem = reduce(mul, input_shape, 1)
         input_size = num_elem * input_byte_per_elem
-        # Most GPU algorithms take O(n) space or less, we choose 8N + 4MB as a safe estimation
+        # Most GPU algorithms take O(n) space or less, we choose 8N + 8MB as a safe estimation
         # for algorithm workspace.
         # The current thrust sort implementation may need extra int64 and int32 arrays
         # for temporary data, so we further add this part to the workspace.
         return (
             8 * input_size
-            + 4 * 1024 * 1024
+            + 8 * 1024 * 1024
             + num_elem * (int64_byte_per_elem + int32_byte_per_elem)
         )