David Rientjes
2da02997e0
mm: add dirty_background_bytes and dirty_bytes sysctls ...
This change introduces two new sysctls to /proc/sys/vm:
dirty_background_bytes and dirty_bytes.
dirty_background_bytes is the counterpart to dirty_background_ratio and
dirty_bytes is the counterpart to dirty_ratio.
With growing memory capacities of individual machines, it's no longer
sufficient to specify dirty thresholds as a percentage of the amount of
dirtyable memory over the entire system.
dirty_background_bytes and dirty_bytes specify quantities of memory, in
bytes, that represent the dirty limits for the entire system. If either
of these values is set, its value represents the amount of dirty memory
that is needed to commence either background or direct writeback.
When a `bytes' or `ratio' file is written, its counterpart becomes a
function of the written value. For example, if dirty_bytes is written to
be 8096, 8K of memory is required to commence direct writeback.
dirty_ratio is then functionally equivalent to 8K / the amount of
dirtyable memory:
dirtyable_memory = free pages + mapped pages + file cache
dirty_background_bytes = dirty_background_ratio * dirtyable_memory
-or-
dirty_background_ratio = dirty_background_bytes / dirtyable_memory
AND
dirty_bytes = dirty_ratio * dirtyable_memory
-or-
dirty_ratio = dirty_bytes / dirtyable_memory
Only one of dirty_background_bytes and dirty_background_ratio may be
specified at a time, and only one of dirty_bytes and dirty_ratio may be
specified. When one sysctl is written, the other appears as 0 when read.
The `bytes' files operate on a page size granularity since dirty limits
are compared with ZVC values, which are in page units.
Prior to this change, the minimum dirty_ratio was 5 as implemented by
get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user
written value between 0 and 100. This restriction is maintained, but
dirty_bytes has a lower limit of only one page.
Also prior to this change, the dirty_background_ratio could not equal or
exceed dirty_ratio. This restriction is maintained in addition to
restricting dirty_background_bytes. If either background threshold equals
or exceeds that of the dirty threshold, it is implicitly set to half the
dirty threshold.
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:03 -08:00
Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-03 12:04:39 -08:00
cpumask: convert rest of files in kernel/
2009-01-01 10:12:28 +10:30
Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-03 12:04:39 -08:00
Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-02 11:44:09 -08:00
CRED: Wrap task credential accesses in the core kernel
2008-11-14 10:39:12 +11:00
[PATCH] fix broken timestamps in AVC generated by kernel threads
2008-12-09 02:27:41 -05:00
fixing audit rule ordering mess, part 1
2009-01-04 15:14:41 -05:00
audit: validate comparison operations, store them in sane form
2009-01-04 15:14:42 -05:00
audit: validate comparison operations, store them in sane form
2009-01-04 15:14:42 -05:00
make sure that filterkey of task,always rules is reported
2009-01-04 15:14:42 -05:00
sanitize audit_log_capset()
2009-01-04 15:14:41 -05:00
mm: remove cgroup_mm_owner_callbacks
2009-01-06 15:59:01 -08:00
cgroups: fix probable race with put_css_set[_taskexit] and find_css_set
2008-10-20 08:52:38 -07:00
freezer_cg: disable writing freezer.state of root cgroup
2008-11-12 17:17:16 -08:00
cpumask: convert kernel/compat.c
2009-01-01 10:12:24 +10:30
kernel/configs.c: remove useless comments
2008-10-20 08:52:34 -07:00
stop_machine: introduce stop_machine_create/destroy.
2009-01-05 08:40:14 +10:30
oom: print triggering task's cpuset and mems allowed
2009-01-06 15:58:59 -08:00
CRED: Inaugurate COW credentials
2008-11-14 10:39:23 +11:00
User namespaces: set of cleanups (v2)
2008-11-24 18:57:41 -05:00
schedstat: consolidate per-task cpu runtime stats
2008-12-18 13:54:01 +01:00
kernel/dma.c: remove a CVS keyword
2008-10-16 11:21:30 -07:00
proc: move /proc/execdomains to kernel/exec_domain.c
2008-10-23 14:30:41 +04:00
mm: remove cgroup_mm_owner_callbacks
2009-01-06 15:59:01 -08:00
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
aio: make the lookup_ioctx() lockless
2008-12-29 08:29:50 +01:00
freezer_cg: use thaw_process() in unfreeze_cgroup()
2008-10-30 11:38:45 -07:00
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
CRED: Use RCU to access another task's creds and to release a task's own creds
2008-11-14 10:39:19 +11:00
Merge branch 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-31 09:00:59 -08:00
allow stripping of generated symbols under CONFIG_KALLSYMS_ALL
2008-12-19 22:47:10 +01:00
container freezer: implement freezer cgroup subsystem
2008-10-20 08:52:34 -07:00
rcu: provide RCU options on non-preempt architectures too
2008-12-25 09:31:28 +01:00
cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core
2009-01-01 10:12:15 +10:30
kgdb: call touch_softlockup_watchdog on resume
2008-10-06 13:50:59 -05:00
CRED: Inaugurate COW credentials
2008-11-14 10:39:23 +11:00
kernel/kprobes.c: don't pad kretprobe_table_locks[] on uniprocessor builds
2008-11-12 17:17:17 -08:00
profiling: dynamically enable readprofile at runtime
2008-10-16 11:21:31 -07:00
tracepoints: add DECLARE_TRACE() and DEFINE_TRACE()
2008-11-16 09:01:36 +01:00
KSYM_SYMBOL_LEN fixes
2008-12-10 08:01:54 -08:00
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
lockstat: contend with points
2008-10-20 15:43:10 +02:00
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
markers/tracpoints: fix non-modular build
2008-11-16 09:52:03 +01:00
module: convert to stop_machine_create/destroy.
2009-01-05 08:40:15 +10:30
mutex: __used is needed for function referenced only from inline asm
2008-11-24 10:00:28 +01:00
Merge commit 'v2.6.28-rc6' into core/debug
2008-11-26 08:22:50 +01:00
User namespaces: set of cleanups (v2)
2008-11-24 18:57:41 -05:00
Merge branch 'core/debug' into core/core
2008-12-25 13:53:11 +01:00
Fix compile warning in kernel/params.c
2008-10-23 12:09:00 -07:00
Merge commit 'v2.6.28' into core/core
2008-12-25 13:51:46 +01:00
Merge branches 'timers/clocksource', 'timers/hpet', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/rtc' into timers/core
2008-12-25 18:02:25 +01:00
printk: fix discarding message when recursion_bug
2008-12-19 22:52:47 +01:00
cpumask: convert kernel/profile.c
2009-01-01 10:12:27 +10:30
Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-28 12:21:10 -08:00
cpumask: convert RCU implementations, fix
2009-01-03 18:59:25 +01:00
rcupdate: fix bug of rcu_barrier*()
2008-10-21 15:59:53 +02:00
cpumask: convert RCU implementations
2009-01-01 10:12:26 +10:30
"Tree RCU": scalable classic RCU implementation
2008-12-18 21:56:04 +01:00
cpumask: convert RCU implementations
2009-01-01 10:12:26 +10:30
"Tree RCU": scalable classic RCU implementation
2008-12-18 21:56:04 +01:00
"Tree RCU": scalable classic RCU implementation
2008-12-18 21:56:04 +01:00
relayfs: fix infinite loop with splice()
2008-12-10 08:01:52 -08:00
resources: skip sanity check of busy resources
2008-12-16 23:30:49 +01:00
Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-03 12:04:39 -08:00
Revert "sched_clock: prevent scd->clock from moving backwards"
2008-12-14 16:23:17 -08:00
sched: convert struct cpupri_vec cpumask_var_t.
2008-11-24 17:52:22 +01:00
sched: convert struct cpupri_vec cpumask_var_t.
2008-11-24 17:52:22 +01:00
sched: add uid information to sched_debug for CONFIG_USER_SCHED
2008-12-01 20:39:50 +01:00
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask
2009-01-03 18:53:31 +01:00
sched: backward looking buddy
2008-11-05 10:30:14 +01:00
sched: add CONFIG_SMP consistency
2008-10-22 10:01:52 +02:00
sched: put back some stack hog changes that were undone in kernel/sched.c
2009-01-03 19:00:09 +01:00
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask
2009-01-03 18:53:31 +01:00
Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-28 12:21:10 -08:00
cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core
2009-01-01 10:12:15 +10:30
Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-01-03 12:04:39 -08:00
cpumask: convert rest of files in kernel/
2009-01-01 10:12:28 +10:30
stacktrace: provide save_stack_trace_tsk() weak alias
2008-12-25 11:44:43 +01:00
stop_machine: introduce stop_machine_create/destroy.
2009-01-05 08:40:14 +10:30
Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-30 16:10:19 -08:00
reintroduce accept4
2008-11-19 18:49:57 -08:00
mm: add dirty_background_bytes and dirty_bytes sysctls
2009-01-06 15:59:03 -08:00
[XFS] remove restricted chown parameter from xfs linux
2008-10-30 18:30:09 +11:00
cpumask: convert rest of files in kernel/
2009-01-01 10:12:28 +10:30
[PATCH] idle cputime accounting
2008-12-31 15:11:46 +01:00
markers/tracpoints: fix non-modular build
2008-11-16 09:52:03 +01:00
CRED: Use RCU to access another task's creds and to release a task's own creds
2008-11-14 10:39:19 +11:00
CRED: Wrap current->cred and a few other accessors
2008-11-14 10:39:18 +11:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2008-12-28 12:27:58 -08:00
User namespaces: set of cleanups (v2)
2008-11-24 18:57:41 -05:00
sysctl: simplify ->strategy
2008-10-16 11:21:47 -07:00
wait: kill is_sync_wait()
2008-10-16 11:21:31 -07:00
cpumask: convert kernel/workqueue.c
2009-01-01 10:12:25 +10:30
2da02997e0