9f68395333
Now that runnable_load_avg has been removed, we can replace it by a new signal that will highlight the runnable pressure on a cfs_rq. This signal track the waiting time of tasks on rq and can help to better define the state of rqs. At now, only util_avg is used to define the state of a rq: A rq with more that around 80% of utilization and more than 1 tasks is considered as overloaded. But the util_avg signal of a rq can become temporaly low after that a task migrated onto another rq which can bias the classification of the rq. When tasks compete for the same rq, their runnable average signal will be higher than util_avg as it will include the waiting time and we can use this signal to better classify cfs_rqs. The new runnable_avg will track the runnable time of a task which simply adds the waiting time to the running time. The runnable _avg of cfs_rq will be the /Sum of se's runnable_avg and the runnable_avg of group entity will follow the one of the rq similarly to util_avg. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>" Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Valentin Schneider <valentin.schneider@arm.com> Cc: Phil Auld <pauld@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Link: https://lore.kernel.org/r/20200224095223.13361-9-mgorman@techsingularity.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.