diff --git a/tools/lib/filereader.py b/tools/lib/filereader.py
index 826bce5fdf..5c9b375bb2 100644
--- a/tools/lib/filereader.py
+++ b/tools/lib/filereader.py
@@ -1,9 +1,4 @@
-import os
-
-if "COMMA_PARALLEL_DOWNLOADS" in os.environ:
-  from tools.lib.url_file_parallel import URLFileParallel as URLFile
-else:
-  from tools.lib.url_file import URLFile  # type: ignore
+from tools.lib.url_file import URLFile
 
 
 def FileReader(fn, debug=False):
diff --git a/tools/lib/url_file_parallel.py b/tools/lib/url_file_parallel.py
deleted file mode 100644
index f6dc37a3b4..0000000000
--- a/tools/lib/url_file_parallel.py
+++ /dev/null
@@ -1,81 +0,0 @@
-# pylint: skip-file
-
-import os
-import pycurl
-from tools.lib.url_file import URLFile
-from io import BytesIO
-from tenacity import retry, wait_random_exponential, stop_after_attempt
-
-from multiprocessing import Pool
-
-
-class URLFileParallel(URLFile):
-  def __init__(self, url, debug=False):
-    self._length = None
-    self._url = url
-    self._pos = 0
-    self._local_file = None
-
-  def get_curl(self):
-    curl = pycurl.Curl()
-    curl.setopt(pycurl.NOSIGNAL, 1)
-    curl.setopt(pycurl.TIMEOUT_MS, 500000)
-    curl.setopt(pycurl.FOLLOWLOCATION, True)
-    return curl
-
-  @retry(wait=wait_random_exponential(multiplier=1, max=5), stop=stop_after_attempt(3), reraise=True)
-  def get_length(self):
-    if self._length is not None:
-      return self._length
-
-    c = self.get_curl()
-    c.setopt(pycurl.URL, self._url)
-    c.setopt(c.NOBODY, 1)
-    c.perform()
-
-    length = int(c.getinfo(c.CONTENT_LENGTH_DOWNLOAD))
-    self._length = length
-    return length
-
-  @retry(wait=wait_random_exponential(multiplier=1, max=5), stop=stop_after_attempt(3), reraise=True)
-  def download_chunk(self, start, end=None):
-    if end is None:
-      trange = f'bytes={start}-'
-    else:
-      trange = f'bytes={start}-{end}'
-
-    dats = BytesIO()
-    c = self.get_curl()
-    c.setopt(pycurl.URL, self._url)
-    c.setopt(pycurl.WRITEDATA, dats)
-    c.setopt(pycurl.HTTPHEADER, ["Range: " + trange, "Connection: keep-alive"])
-    c.perform()
-
-    response_code = c.getinfo(pycurl.RESPONSE_CODE)
-    if response_code != 206 and response_code != 200:
-      raise Exception("Error {} ({}): {}".format(response_code, self._url, repr(dats.getvalue())[:500]))
-
-    return dats.getvalue()
-
-  def read(self, ll=None):
-    start = self._pos
-    end = None if ll is None else self._pos + ll - 1
-    max_threads = int(os.environ.get("COMMA_PARALLEL_DOWNLOADS", "0"))
-
-    end = self.get_length() if end is None else end
-    threads = min((end - start) // (512 * 1024), max_threads)  # At least 512k per thread
-
-    if threads > 1:
-      chunk_size = (end - start) // threads
-      chunks = [
-        (start + chunk_size * i,
-         start + chunk_size * (i + 1) - 1 if i != threads - 1 else end)
-        for i in range(threads)]
-
-      with Pool(threads) as pool:
-        ret = b"".join(pool.starmap(self.download_chunk, chunks))
-    else:
-      ret = self.download_chunk(start, end)
-
-    self._pos += len(ret)
-    return ret