diff --git a/swh/loader/pypi/client.py b/swh/loader/pypi/client.py
--- a/swh/loader/pypi/client.py
+++ b/swh/loader/pypi/client.py
@@ -290,7 +290,7 @@
 
             h = hashutil.MultiHash(length=length)
             with open(filepath, 'wb') as f:
-                for chunk in r.iter_content():
+                for chunk in r.iter_content(chunk_size=None):
                     h.update(chunk)
                     f.write(chunk)