2f69555315
Eric Dumazet says:
====================
tcp: take a bit more care of backlog stress
While working on the SACK compression issue Jean-Louis Dupond
reported, we found that his linux box was suffering very hard
from tail drops on the socket backlog queue.
First patch hints the compiler about sack flows being the norm.
Second patch changes non-sack code in preparation of the ack
compression.
Third patch fixes tcp_space() to take backlog into account.
Fourth patch is attempting coalescing when a new packet must
be added to the backlog queue. Cooking bigger skbs helps
to keep backlog list smaller and speeds its handling when
user thread finally releases the socket lock.
v3: Neal/Yuchung feedback addressed :
Do not aggregate if any skb has URG bit set.
Do not aggregate if the skbs have different ECE/CWR bits
v2: added feedback from Neal : tcp: take care of compressed acks in tcp_add_reno_sack()
added : tcp: hint compiler about sack flows
added : tcp: make tcp_space() aware of socket backlog
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.