Re: Integrating cpusets and cpu isolation [was Re: [CPUISOL] CPU isolation extensions]

[Paul Jackson <pj@sgi.com>]

Max wrote:
> Here is the list of things of issues with sched_load_balance flag from CPU isolation 
> perspective:

A separate thread happened to start up on lkml.org, shortly after
yours, that went into this in considerable detail.

For example, the interaction of cpusets, sched_load_balance,
sched_domains and real time scheduling is examined in some detail on
this thread.  Everyone participating on that thread learned something
(we all came into it with less than a full picture of what's there.)

I would encourage you to read it closely.  For example, the scheduler
code should not be trying to access per-cpuset attributes such as
the sched_load_balance flag (you are correct that this would be
difficult to do because of the locking; however by design, that is
not to be done.)

This thread begins at:

    scheduler scalability - cgroups, cpusets and load-balancing
    http://lkml.org/lkml/2008/1/29/60

Too bad we didn't think to include you in the CC list of that
thread from the beginning.

-- 
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                  Paul Jackson <pj@sgi.com> 1.940.382.4214