Paul Turner
d8b4986d3d
sched: Return unused runtime on group dequeue ...
When a local cfs_rq blocks we return the majority of its remaining quota to the
global bandwidth pool for use by other runqueues.
We do this only when the quota is current and there is more than
min_cfs_rq_quota [1ms by default] of runtime remaining on the rq.
In the case where there are throttled runqueues and we have sufficient
bandwidth to meter out a slice, a second timer is kicked off to handle this
delivery, unthrottling where appropriate.
Using a 'worst case' antagonist which executes on each cpu
for 1ms before moving onto the next on a fairly large machine:
no quota generations:
197.47 ms /cgroup/a/cpuacct.usage
199.46 ms /cgroup/a/cpuacct.usage
205.46 ms /cgroup/a/cpuacct.usage
198.46 ms /cgroup/a/cpuacct.usage
208.39 ms /cgroup/a/cpuacct.usage
Since we are allowed to use "stale" quota our usage is effectively bounded by
the rate of input into the global pool and performance is relatively stable.
with quota generations [1s increments]:
119.58 ms /cgroup/a/cpuacct.usage
119.65 ms /cgroup/a/cpuacct.usage
119.64 ms /cgroup/a/cpuacct.usage
119.63 ms /cgroup/a/cpuacct.usage
119.60 ms /cgroup/a/cpuacct.usage
The large deficit here is due to quota generations (/intentionally/) preventing
us from now using previously stranded slack quota. The cost is that this quota
becomes unavailable.
with quota generations and quota return:
200.09 ms /cgroup/a/cpuacct.usage
200.09 ms /cgroup/a/cpuacct.usage
198.09 ms /cgroup/a/cpuacct.usage
200.09 ms /cgroup/a/cpuacct.usage
200.06 ms /cgroup/a/cpuacct.usage
By returning unused quota we're able to both stably consume our desired quota
and prevent unintentional overages due to the abuse of slack quota from
previous quota periods (especially on a large machine).
Signed-off-by: Paul Turner <pjt@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110721184758.306848658@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-14 12:03:54 +02:00
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb
2011-08-01 13:39:40 -10:00
perf: Remove perf_event_attr::type check
2011-07-21 20:41:55 +02:00
gcov: disable CONSTRUCTORS for UML
2011-07-26 16:49:45 -07:00
Merge branch 'imx/dt' into next/dt
2011-07-28 15:25:46 +00:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
2011-07-25 13:56:39 -07:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-07-22 16:52:18 -07:00
Merge branch 'linus' into perf/urgent
2011-08-05 10:33:55 +02:00
async: Fixed an include coding style issue
2011-06-14 22:48:46 -04:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
audit_tree,rcu: Convert call_rcu(__put_tree) to kfree_rcu()
2011-07-20 14:10:11 -07:00
kill path_lookup()
2011-03-14 09:15:23 -04:00
netlink: kill loginuid/sessionid/sid members from struct netlink_skb_parms
2011-03-03 10:55:40 -08:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
memcg: remove direct page_cgroup-to-page pointer
2011-03-23 19:46:28 -07:00
Merge branch 'master' into next
2011-05-19 18:51:57 +10:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
2011-07-27 19:26:38 -07:00
cgroups: add per-thread subsystem callbacks
2011-05-26 17:12:34 -07:00
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
2011-07-30 00:08:53 -07:00
kernel/configs.c: include MODULE_*() when CONFIG_IKCONFIG_PROC=n
2011-07-25 20:57:15 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn
2011-03-23 19:47:19 -07:00
move RLIMIT_NPROC check from set_user() to do_execve_common()
2011-08-11 11:24:42 -07:00
KVM: Steal time implementation
2011-07-14 12:59:14 +03:00
ipc: introduce shm_rmid_forced sysctl
2011-07-26 16:49:44 -07:00
extable, core_kernel_data(): Make sure all archs define _sdata
2011-05-20 08:56:56 +02:00
move RLIMIT_NPROC check from set_user() to do_execve_common()
2011-08-11 11:24:42 -07:00
Freezer: Use SMP barriers
2011-05-17 23:19:17 +02:00
Merge branch 'linus' into core/urgent
2011-08-04 09:09:27 +02:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
hrtimers: Fix typo causing erratic timers
2011-05-25 15:31:58 -07:00
watchdog, hung_task_timeout: Add Kconfig configurable default
2011-04-28 09:13:17 +02:00
irq_work: Use per cpu atomics instead of regular atomics
2010-12-18 15:54:48 +01:00
jump_label: Fix jump_label update for modules
2011-06-29 09:59:17 -04:00
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-03-25 17:52:22 -07:00
arch:Kconfig.locks Remove unused config option.
2011-04-10 17:01:05 +02:00
sched: Isolate preempt counting in its own config option
2011-06-10 15:15:40 +02:00
treewide: Convert uses of struct resource to resource_size(ptr)
2011-06-10 14:55:36 +02:00
Boot up with usermodehelper disabled
2011-08-03 22:03:29 -10:00
kprobes: Return -ENOENT if probe point doesn't exist
2011-07-15 15:11:47 -04:00
kernel/ksysfs.c: expose file_caps_enabled in sysfs
2011-04-19 16:45:51 -07:00
cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed
2011-05-28 17:02:57 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
lockdep: Clear whole lockdep_map on initialization
2011-08-04 10:17:56 +02:00
lockdep: Remove unused 'factor' variable from lockdep_stats_show()
2011-03-23 13:54:47 +01:00
jump label: Reduce the cycle count by changing the link order
2011-08-05 23:57:33 +02:00
module: add /sys/module/<name>/uevent files
2011-07-24 22:06:04 +09:30
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
lockdep, mutex: provide mutex_lock_nest_lock
2011-05-25 08:39:17 -07:00
mutex: Use p->on_cpu for the adaptive spin
2011-04-14 08:52:33 +02:00
notifiers: sys: move reboot notifiers into reboot.h
2011-07-25 20:57:14 -07:00
make sure that nsproxy_cache is initialized early enough
2011-07-20 01:44:07 -04:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
panic: panic=-1 for immediate reboot
2011-07-26 16:49:45 -07:00
module: add /sys/module/<name>/uevent files
2011-07-24 22:06:04 +09:30
rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check
2011-07-08 22:21:58 +02:00
pidns: call pid_ns_prepare_proc() from create_pid_namespace()
2011-03-23 19:46:58 -07:00
plist: Remove the need to supply locks to plist heads
2011-07-08 14:02:53 +02:00
hrtimers: Avoid touching inactive timer bases
2011-05-23 13:59:54 +02:00
posix-timers: RCU conversion
2011-05-24 12:10:51 +02:00
cap_syslog: don't use WARN_ONCE for CAP_SYS_ADMIN deprecation warning
2011-08-09 18:22:22 -07:00
kernel/profile.c: remove some duplicate code from profile_hits()
2011-05-26 17:12:37 -07:00
connector: add an event for monitoring process tracers
2011-07-18 21:38:33 +02:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
sanitize <linux/prefetch.h> usage
2011-05-20 12:50:29 -07:00
rcu: Converge TINY_RCU expedited and normal boosting
2011-05-05 23:16:58 -07:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
rcu: Prevent RCU callbacks from executing before scheduler initialized
2011-07-13 08:17:56 -07:00
rcu: Move RCU_BOOST #ifdefs to header file
2011-06-16 16:12:05 -07:00
softirq,rcu: Inform RCU of irq_exit() activity
2011-07-20 10:50:12 -07:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
memcg: res_counter_read_u64(): fix potential races on 32-bit machines
2011-03-23 19:46:22 -07:00
resources: Add lookup_resource()
2011-07-30 21:21:39 +02:00
rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-27 21:13:51 -05:00
rtmutex: tester: Remove the remaining BKL leftovers
2011-02-22 22:07:22 +01:00
plist: Remove the need to supply locks to plist heads
2011-07-08 14:02:53 +02:00
rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-27 21:13:51 -05:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
sched: Return unused runtime on group dequeue
2011-08-14 12:03:54 +02:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
sched: Skip autogroup when looking for all rt sched groups
2011-07-01 10:39:08 +02:00
sched/cpupri: Remove cpupri->pri_active
2011-08-14 12:01:11 +02:00
sched/cpupri: Remove cpupri->pri_active
2011-08-14 12:01:11 +02:00
sched: Get rid of lock_depth
2011-04-24 13:18:38 +02:00
sched: Return unused runtime on group dequeue
2011-08-14 12:03:54 +02:00
sched: Kill WAKEUP_PREEMPT
2011-08-14 12:00:41 +02:00
sched: Drop the rq argument to sched_class::select_task_rq()
2011-04-14 08:52:36 +02:00
sched: Implement hierarchical task accounting for SCHED_OTHER
2011-08-14 12:01:13 +02:00
sched: More sched_domain iterations fixes
2011-05-28 17:02:54 +02:00
sched: Implement hierarchical task accounting for SCHED_OTHER
2011-08-14 12:01:13 +02:00
signals: sys_ssetmask/sys_rt_sigsuspend should use set_current_blocked()
2011-07-27 12:53:36 -07:00
generic-ipi: Fix kexec boot crash by initializing call_single_queue before enabling interrupts
2011-06-17 10:17:12 +02:00
softirq,rcu: Inform RCU of irq_exit() activity
2011-07-20 10:50:12 -07:00
rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
2011-01-14 04:56:49 -08:00
stack_trace: Add weak save_stack_trace_regs()
2011-06-14 22:48:52 -04:00
atomic: use <linux/atomic.h>
2011-07-26 16:49:47 -07:00
move RLIMIT_NPROC check from set_user() to do_execve_common()
2011-08-11 11:24:42 -07:00
ipc: Add missing sys_ni entries for ipc/compat.c functions
2011-05-20 13:53:02 -07:00
sched: Accumulate per-cfs_rq cpu usage and charge against bandwidth
2011-08-14 12:03:26 +02:00
open-style analog of vfs_path_lookup()
2011-03-14 09:15:28 -04:00
sysctl_check: drop dead code
2011-03-23 19:46:51 -07:00
taskstats: add_del_listener() should ignore !valid listeners
2011-08-03 14:25:20 -10:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2011-03-15 18:53:35 -07:00
timers: Consider slack value in mod_timer()
2011-06-03 15:02:32 +02:00
jump label: Introduce static_branch() interface
2011-04-04 12:48:08 -04:00
userns: user namespaces: convert several capable() calls
2011-03-23 19:47:08 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
userns: add a user_namespace as creator/owner of uts_namespace
2011-03-23 19:46:59 -07:00
user_ns: improve the user_ns on-the-slab packaging
2011-01-13 08:03:18 -08:00
ns proc: Add support for the uts namespace
2011-05-10 14:35:35 -07:00
Fix common misspellings
2011-03-31 11:26:23 -03:00
perf, x86: P4 PMU - Introduce event alias feature
2011-07-14 17:25:04 -04:00
Merge branch 'for-3.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2011-07-22 15:07:15 -07:00
d8b4986d3d