linux/kernel
Peter Williams 50ddd96917 [PATCH] sched: modify move_tasks() to improve load balancing outcomes
Problem:

The move_tasks() function is designed to move UP TO the amount of load it
is asked to move and in doing this it skips over tasks looking for ones
whose load weights are less than or equal to the remaining load to be
moved.  This is (in general) a good thing but it has the unfortunate result
of breaking one of the original load balancer's good points: namely, that
(within the limits imposed by the active/expired array model and the fact
the expired is processed first) it moves high priority tasks before low
priority ones and this means there's a good chance (see active/expired
problem for why it's only a chance) that the highest priority task on the
queue but not actually on the CPU will be moved to the other CPU where (as
a high priority task) it may preempt the current task.

Solution:

Modify move_tasks() so that high priority tasks are not skipped when moving
them will make them the highest priority task on their new run queue.

Signed-off-by: Peter Williams <pwil3058@bigpond.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:44 -07:00
..
irq [PATCH] adjust handle_IRR_event() return type 2006-06-23 07:43:08 -07:00
power [PATCH] pm_trace is dangerous 2006-06-27 17:32:35 -07:00
time [PATCH] time: rename clocksource functions 2006-06-26 09:58:21 -07:00
.gitignore
acct.c [PATCH] fix kernel-doc in kernel/ dir 2006-06-27 17:32:39 -07:00
audit.c [PATCH] spin/rwlock init cleanups 2006-06-27 17:32:39 -07:00
audit.h [PATCH] log more info for directory entry change events 2006-06-20 05:25:28 -04:00
auditfilter.c [PATCH] log more info for directory entry change events 2006-06-20 05:25:28 -04:00
auditsc.c [PATCH] fix kernel-doc in kernel/ dir 2006-06-27 17:32:39 -07:00
capability.c [PATCH] refactor capable() to one implementation, add __capable() helper 2006-03-25 08:22:56 -08:00
compat.c [PATCH] N32 sigset and __COMPAT_ENDIAN_SWAP__ 2006-06-25 10:01:15 -07:00
configs.c
cpu.c [PATCH] cpu hotplug: make [un]register_cpu_notifier init time only 2006-06-27 17:32:41 -07:00
cpuset.c [PATCH] proc: Use struct pid not struct task_ref 2006-06-26 09:58:26 -07:00
dma.c
exec_domain.c [PATCH] Fix module refcount leak in __set_personality() 2006-03-24 07:33:30 -08:00
exit.c [PATCH] proc: Rewrite the proc dentry flush on exit optimization 2006-06-26 09:58:24 -07:00
extable.c [PATCH] symbol_put_addr() locks kernel 2006-05-15 11:20:55 -07:00
fork.c [PATCH] coredump: copy_process: don't check SIGNAL_GROUP_EXIT 2006-06-26 09:58:27 -07:00
futex_compat.c [PATCH] futex: check and validate timevals 2006-03-31 12:18:59 -08:00
futex.c [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
hrtimer.c [PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17 2006-06-27 17:32:41 -07:00
itimer.c [PATCH] hrtimers: remove data field 2006-03-26 08:57:03 -08:00
kallsyms.c
Kconfig.hz
Kconfig.preempt
kexec.c [PATCH] Add a sysfs file to determine if a kexec kernel is loaded 2006-06-23 07:43:02 -07:00
kfifo.c
kmod.c [PATCH] wait_for_helper: trivial style cleanup 2006-03-28 18:36:41 -08:00
kprobes.c [PATCH] Notify page fault call chain 2006-06-26 09:58:22 -07:00
ksysfs.c [PATCH] Add a sysfs file to determine if a kexec kernel is loaded 2006-06-23 07:43:02 -07:00
kthread.c [PATCH] kthread: move kernel-doc and put it into DocBook 2006-06-25 10:01:24 -07:00
Makefile Merge branch 'x86-64' 2006-06-26 10:51:09 -07:00
module.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild 2006-06-26 11:05:15 -07:00
mutex-debug.c [PATCH] poison: add & use more constants 2006-06-27 17:32:38 -07:00
mutex-debug.h [PATCH] work around ppc64 bootup bug by making mutex-debugging save/restore irqs 2006-06-26 09:58:16 -07:00
mutex.c [PATCH] work around ppc64 bootup bug by making mutex-debugging save/restore irqs 2006-06-26 09:58:16 -07:00
mutex.h [PATCH] work around ppc64 bootup bug by making mutex-debugging save/restore irqs 2006-06-26 09:58:16 -07:00
panic.c [PATCH] the scheduled unexport of panic_timeout 2006-04-11 06:18:40 -07:00
params.c [PATCH] Change dash2underscore() return value to char 2006-03-28 09:16:03 -08:00
pid.c [PATCH] pidhash: Refactor the pid hash table 2006-03-31 12:19:00 -08:00
posix-cpu-timers.c [PATCH] arm_timer: remove a racy and obsolete PF_EXITING check 2006-06-17 10:52:13 -07:00
posix-timers.c [PATCH] hrtimers: remove data field 2006-03-26 08:57:03 -08:00
printk.c [PATCH] printk time parameter 2006-06-25 10:01:13 -07:00
profile.c [PATCH] cpu hotplug: revert init patch submitted for 2.6.17 2006-06-27 17:32:40 -07:00
ptrace.c [PATCH] coredump: kill ptrace related stuff 2006-06-26 09:58:27 -07:00
rcupdate.c [PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17 2006-06-27 17:32:41 -07:00
rcutorture.c [PATCH] rcutorture: add call_rcu_bh() operations 2006-06-27 17:32:40 -07:00
relay.c [PATCH] relay: consolidate sendfile() and read() code 2006-03-23 19:58:45 +01:00
resource.c [PATCH] catch valid mem range at onlining memory 2006-06-27 17:32:36 -07:00
sched.c [PATCH] sched: modify move_tasks() to improve load balancing outcomes 2006-06-27 17:32:44 -07:00
seccomp.c
signal.c [PATCH] coredump: kill ptrace related stuff 2006-06-26 09:58:27 -07:00
softirq.c [PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17 2006-06-27 17:32:41 -07:00
softlockup.c [PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17 2006-06-27 17:32:41 -07:00
spinlock.c [PATCH] BUILD_LOCK_OPS: cleanup preempt_disable() usage 2006-03-23 07:38:16 -08:00
stop_machine.c [PATCH] kthread: convert stop_machine into a kthread 2006-06-25 10:01:22 -07:00
sys_ni.c [PATCH] sys_move_pages: 32bit support (i386, x86_64) 2006-06-23 07:42:53 -07:00
sys.c [PATCH] kernel/sys.c: cleanups 2006-06-25 10:01:06 -07:00
sysctl.c [PATCH] vdso: randomize the i386 vDSO by moving it into a vma 2006-06-27 17:32:38 -07:00
time.c [PATCH] Time: Introduce arch generic time accessors 2006-06-26 09:58:20 -07:00
timer.c [PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17 2006-06-27 17:32:41 -07:00
uid16.c [PATCH] Add more prevent_tail_call() 2006-04-19 16:27:18 -07:00
unwind.c [PATCH] x86_64: allow unwinder to build without module support 2006-06-26 10:48:18 -07:00
user.c [PATCH] selinux: add hooks for key subsystem 2006-06-22 15:05:55 -07:00
wait.c
workqueue.c [PATCH] cpu hotplug: revert init patch submitted for 2.6.17 2006-06-27 17:32:40 -07:00