commit 0237265e8287141c40faa8719da3a2d21d511d0d
author Andrew Svetlov <andrew.svetlov@gmail.com> Sat Jun 15 14:05:35 2019 +0300
committer GitHub <noreply@github.com> Sat Jun 15 14:05:35 2019 +0300
tree 5df00acc5a5d5e061d83abd85f1134e8d73e0aba
parent ef2152354f03a165c5e3adb53e2276934fabd50a

Use threadpool for reading from file in sendfile fallback mode (#14076)

Lib/asyncio/base_events.py

diff --git a/Lib/asyncio/base_events.py b/Lib/asyncio/base_events.py
index 90de858..14b80bd 100644
--- a/Lib/asyncio/base_events.py
+++ b/Lib/asyncio/base_events.py
@@ -1141,7 +1141,7 @@
                     if blocksize <= 0:
                         return total_sent
                 view = memoryview(buf)[:blocksize]
-                read = file.readinto(view)
+                read = await self.run_in_executor(None, file.readinto, view)
                 if not read:
                     return total_sent  # EOF
                 await proto.drain()

Misc/NEWS.d/next/Library/2019-06-14-13-30-47.bpo-37280.Fxur0F.rst

diff --git a/Misc/NEWS.d/next/Library/2019-06-14-13-30-47.bpo-37280.Fxur0F.rst b/Misc/NEWS.d/next/Library/2019-06-14-13-30-47.bpo-37280.Fxur0F.rst
new file mode 100644
index 0000000..7cdc56a
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-06-14-13-30-47.bpo-37280.Fxur0F.rst
@@ -0,0 +1 @@
+Use threadpool for reading from file for sendfile fallback mode.