af8c8a450b
This commit adds a test for FIN_ACK process races related reconnection
latency spike issues. The issue has described and solved by the
previous commit ("tcp: Reduce SYN resend delay if a suspicous ACK is
received").
The test program is configured with a server and a client process. The
server creates and binds a socket to a port that dynamically allocated,
listen on it, and start a infinite loop. Inside the loop, it accepts
connection, reads 4 bytes from the socket, and closes the connection.
The client is constructed as an infinite loop. Inside the loop, it
creates a socket with LINGER and NODELAY option, connect to the server,
send 4 bytes data, try read some data from server. After the read()
returns, it measure the latency from the beginning of this loop to this
point and if the latency is larger than 1 second (spike), print a
message.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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.