diff --git a/adrtlib/benchmark/chart.py b/adrtlib/benchmark/chart.py
old mode 100644
new mode 100755
index ff9de3c..96d0b2b
--- a/adrtlib/benchmark/chart.py
+++ b/adrtlib/benchmark/chart.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+from typing import TypedDict
 import json
 import matplotlib.pyplot as plt
 from matplotlib.axes import Axes
@@ -8,31 +10,58 @@
     "fht2ids2": "tab:red",
     "fht2idt": "tab:orange",
     "fht2ds": "tab:green",
+    "fht2dt": "tab:cyan",
 }
 
 
-def main():
-    with open("/home/senyai/projects/adrt/adrtlib/build/adrtlib.json") as f:
-        root = json.loads(f.read())
+class Benchmark(TypedDict):
+    name: str
+    cpu_time: float
+    time_unit: str
+    bytes_per_second: float
 
+
+class GoogleBenchmark(TypedDict):
+    benchmarks: list[Benchmark]
+
+
+def _get_alg_name(name: str) -> tuple[str, int]:
+    name = name.removeprefix("BM_")
+    func, extra, size = name.split("/")
+    if extra.startswith(("ds_", "dt")):
+        alg_name = f"{func}{extra[1]}_{extra[3:]}"
+    else:
+        alg_name = f"{func}_{extra}"
+    return alg_name, int(size)
+
+
+def _process(
+    root: GoogleBenchmark, out_path: str, median: bool, n: int
+) -> None:
     points_ms = defaultdict[str, dict[int, float]](dict[int, float])
     points_bytes_per_second = defaultdict[str, dict[int, float]](
         dict[int, float]
     )
+
     for benchmark in root["benchmarks"]:
-        name: str = benchmark["name"]
-        try:
-            alg, recursion, size = name.split("/")
-        except ValueError:
-            recursion = "non_recursive"
-            alg, size = name.split("/")
-        alg_name = alg.removeprefix("BM_") + "_" + recursion
-
-        points_ms[alg_name][int(size)] = benchmark["cpu_time"]
-        points_bytes_per_second[alg_name][int(size)] = benchmark[
+        name = benchmark["name"]
+        if median:
+            if not name.endswith("_median"):
+                continue
+            name = name[:-7]
+        alg_name, size = _get_alg_name(name)
+        if size > n:
+            continue
+
+        points_ms[alg_name][size] = benchmark["cpu_time"]
+        points_bytes_per_second[alg_name][size] = benchmark[
             "bytes_per_second"
         ] / (1024 * 1024 * 1024)
 
+        # something weird happens, that needs investigation. this code for now
+        if points_bytes_per_second[alg_name][size] > 6:
+            points_bytes_per_second[alg_name][size] = 1
+
     fig, (ax1, ax2) = plt.subplots(
         nrows=2, ncols=1, figsize=(10, 16), dpi=96, layout="constrained"
     )
@@ -52,9 +81,25 @@ def do(ax: Axes, points_: defaultdict[str, dict[int, float]]) -> None:
 
     ax1.set_ylabel(f"CPU time, ${benchmark['time_unit']}$")
     ax2.set_ylabel("GiB per second")
-    plt.savefig("adrtlib_benchmark.svg")
-    print("saved adrtlib_benchmark.svg")
+    plt.savefig(out_path)
+    print(f"saved {out_path}")
+
+
+def _main() -> None:
+    from argparse import ArgumentParser
+
+    parser = ArgumentParser()
+    parser.add_argument("json", help="path to benchmark.json")
+    parser.add_argument(
+        "--out", default="adrtlib_benchmark.svg", help="output svg path"
+    )
+    parser.add_argument("--median", action="store_true", help="use _median")
+    parser.add_argument("--n", type=int, default=9999999, help="limit N")
+    args = parser.parse_args()
+    with open(args.json, "r") as f:
+        data = json.load(f)
+    _process(data, args.out, args.median, args.n)
 
 
 if __name__ == "__main__":
-    main()
+    _main()