7298de9cd7
The ingress mode is meant to be enabled when CAKE runs downlink of the actual bottleneck (such as on an IFB device). The mode changes the shaper to also account dropped packets to the shaped rate, as these have already traversed the bottleneck. Enabling ingress mode will also tune the AQM to always keep at least two packets queued *for each flow*. This is done by scaling the minimum queue occupancy level that will disable the AQM by the number of active bulk flows. The rationale for this is that retransmits are more expensive in ingress mode, since dropped packets have to traverse the bottleneck again when they are retransmitted; thus, being more lenient and keeping a minimum number of packets queued will improve throughput in cases where the number of active flows are so large that they saturate the bottleneck even at their minimum window size. This commit also adds a separate switch to enable ingress mode rate autoscaling. If enabled, the autoscaling code will observe the actual traffic rate and adjust the shaper rate to match it. This can help avoid latency increases in the case where the actual bottleneck rate decreases below the shaped rate. The scaling filters out spikes by an EWMA filter. Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> 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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.