mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-05 20:33:49 -04:00
966a675da8
I noticed that a handful of NFSv3 fstests were taking an
unexpectedly long time to run. Troubleshooting showed that the
server's TCP window closed and never re-opened, which caused the
client to trigger an RPC retransmit timeout after 180 seconds.
The client's recovery action was to establish a fresh connection
and retransmit the timed-out requests. This worked, but it adds a
long delay.
I tracked the problem to the commit that attempted to reduce the
rate at which the network layer delivers TCP socket data_ready
callbacks. Under most circumstances this change worked as expected,
but for NFSv3, which has no session or other type of throttling, it
can overwhelm the receiver on occasion.
I'm sure I could tweak the lowat settings, but the small benefit
doesn't seem worth the bother. Just revert it.
Fixes: 2b877fc53e ("SUNRPC: Reduce thread wake-up rate when receiving large RPC messages")
Cc: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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 reStructuredText 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.