cpython/Misc/NEWS.d/next
Ruben Vorderman 23c0fb8edd
bpo-41586: Add pipesize parameter to subprocess & F_GETPIPE_SZ and F_SETPIPE_SZ to fcntl. (GH-21921)
* Add F_SETPIPE_SZ and F_GETPIPE_SZ to fcntl module
* Add pipesize parameter for subprocess.Popen class

This will allow the user to control the size of the pipes.
On linux the default is 64K. When a pipe is full it blocks for writing.
When a pipe is empty it blocks for reading. On processes that are
very fast this can lead to a lot of wasted CPU cycles. On a typical
Linux system the max pipe size is 1024K which is much better.
For high performance-oriented libraries such as xopen it is nice to
be able to set the pipe size.

The workaround without this feature is to use my_popen_process.stdout.fileno() in
conjuction with fcntl and 1031 (value of F_SETPIPE_SZ) to acquire this behavior.
2020-10-19 16:30:02 -07:00
..
Build Python 3.10.0a1 2020-10-05 18:30:18 +01:00
C API bpo-41845: Move PyObject_GenericGetDict() back into the limited API (GH22646) 2020-10-19 23:47:37 +01:00
Core and Builtins closes bpo-42030: Remove legacy AIX dynload support (GH-22717) 2020-10-16 13:03:28 -05:00
Documentation Python 3.10.0a1 2020-10-05 18:30:18 +01:00
IDLE Python 3.10.0a1 2020-10-05 18:30:18 +01:00
Library bpo-41586: Add pipesize parameter to subprocess & F_GETPIPE_SZ and F_SETPIPE_SZ to fcntl. (GH-21921) 2020-10-19 16:30:02 -07:00
Security bpo-42051: Reject XML entity declarations in plist files (#22760) 2020-10-19 20:13:49 +02:00
Tests bpo-41739: Fix test_logging.test_race_between_set_target_and_flush() (GH-22655) 2020-10-12 00:37:20 +02:00
Tools-Demos Consolidate 3.9.0b1 NEWS in the master branch 2020-05-19 13:33:08 +02:00
Windows bpo-39107: Updated Tcl and Tk to 8.6.10 in Windows installer (GH-22405) 2020-10-19 16:55:10 +01:00
macOS bpo-41471: Ignore invalid prefix lengths in system proxy settings on macOS (GH-22762) 2020-10-19 20:16:21 +02:00