[RFC PATCH 0/3] Series short description - Kernel

This is a discussion on [RFC PATCH 0/3] Series short description - Kernel ; Hi Ingo, Steven, Peter, This series applies roughly to mainline as an enhancement to the sched_rt logic. Peter and I were discussing some of the unecessary overhead in pull_rt_tasks() via IRC, and this is my RFC attempt to address the ...

+ Reply to Thread
Results 1 to 5 of 5

Thread: [RFC PATCH 0/3] Series short description

  1. [RFC PATCH 0/3] Series short description

    Hi Ingo, Steven, Peter,
    This series applies roughly to mainline as an enhancement to the sched_rt
    logic. Peter and I were discussing some of the unecessary overhead in
    pull_rt_tasks() via IRC, and this is my RFC attempt to address the problem.

    I have built/booted this on a 4-way C2D Xeon box and it passes preempt-test.

    Comments, please.

    -Greg

    ---

    Gregory Haskins (3):
    sched: use highest_prio.next to optimize pull operations
    sched: use highest_prio.curr for pull threshold
    sched: track the next-highest priority on each runqueue


    kernel/sched.c | 8 ++-
    kernel/sched_rt.c | 158 +++++++++++++++++++++++++++++++----------------------
    2 files changed, 99 insertions(+), 67 deletions(-)

    --
    Signature
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  2. Re: [RFC PATCH 0/3] Series short description


    * Gregory Haskins wrote:

    > Hi Ingo, Steven, Peter,
    > This series applies roughly to mainline as an enhancement to the sched_rt
    > logic. Peter and I were discussing some of the unecessary overhead in
    > pull_rt_tasks() via IRC, and this is my RFC attempt to address the problem.
    >
    > I have built/booted this on a 4-way C2D Xeon box and it passes preempt-test.
    >
    > Comments, please.


    this direction looks very nifty to me. Peter, do you Ack them?

    Ingo
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  3. Re: [RFC PATCH 0/3] Series short description

    Ingo Molnar wrote:
    > * Gregory Haskins wrote:
    >
    >
    >> Hi Ingo, Steven, Peter,
    >> This series applies roughly to mainline as an enhancement to the sched_rt
    >> logic. Peter and I were discussing some of the unecessary overhead in
    >> pull_rt_tasks() via IRC, and this is my RFC attempt to address the problem.
    >>
    >> I have built/booted this on a 4-way C2D Xeon box and it passes preempt-test.
    >>
    >> Comments, please.
    >>

    >
    > this direction looks very nifty to me. Peter, do you Ack them?
    >
    > Ingo
    >

    [I just noticed that I fat-fingered the -rt list address, so here is a
    link to the thread for those subscribed to -rt]

    http://lkml.org/lkml/2008/11/11/193

    -Greg


    -----BEGIN PGP SIGNATURE-----
    Version: GnuPG v2.0.9 (GNU/Linux)
    Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

    iEYEARECAAYFAkkZ1BcACgkQlOSOBdgZUxnr1gCdESRbOlYbwh QfvGy3/SU/G7p0
    6iwAn0UB67EZYd1/06XdiTWeJxa/Tc3S
    =vfKT
    -----END PGP SIGNATURE-----


  4. Re: [RFC PATCH 0/3] Series short description

    Gregory Haskins wrote:
    > Hi Ingo, Steven, Peter,
    > This series applies roughly to mainline as an enhancement to the sched_rt
    > logic. Peter and I were discussing some of the unecessary overhead in
    > pull_rt_tasks() via IRC, and this is my RFC attempt to address the problem.
    >
    > I have built/booted this on a 4-way C2D Xeon box and it passes preempt-test.


    At first blush it looks reasonable, but do you have any performance numbers?

    Chris
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  5. Re: [RFC PATCH 0/3] Series short description

    Chris Friesen wrote:
    > Gregory Haskins wrote:
    >> Hi Ingo, Steven, Peter,
    >> This series applies roughly to mainline as an enhancement to the
    >> sched_rt
    >> logic. Peter and I were discussing some of the unecessary overhead in
    >> pull_rt_tasks() via IRC, and this is my RFC attempt to address the
    >> problem.
    >>
    >> I have built/booted this on a 4-way C2D Xeon box and it passes
    >> preempt-test.

    >
    > At first blush it looks reasonable, but do you have any performance
    > numbers?


    Hi Chris,
    That is a perfectly reasonable request, but unfortunately I do not
    have any at this time. Its currently all based on the observation that
    pull_rt_tasks() can cause excessive rq->lock contention and the theory
    that this should reduce the cases where that happens. It still needs to
    be proven and quantified, outside of the basic litmus test I gave it
    before posting.

    I will try to get to this ASAP.

    Regards,
    -Greg



    -----BEGIN PGP SIGNATURE-----
    Version: GnuPG v2.0.9 (GNU/Linux)
    Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

    iEYEARECAAYFAkkZ4egACgkQlOSOBdgZUxnEEgCfbc6CY1234H eFa+5Srx6/WQb3
    GuYAmwW+km5A4ktQMG33EmZ2UuVtvP/F
    =XjUL
    -----END PGP SIGNATURE-----


+ Reply to Thread