11:28 a.m.
Hello,
This patch fixes a problem made evident by the debian bug 655843,
'powertop report[s] incorrect "bad" value.'
The issue is that the tunable for the "Power Aware CPU scheduler" has an
outdated target value of "1". That value was correct in linux kernels
before the 2.6.29 release. However, starting with the 2.6.29 release,
the level setting for the scheduler that offered the greatest power
savings was increased to "2" (linux kernel commit:
afb8a9b70b86866a60e08b2956ae4e1406390336). Eventually, due to seemingly
poor code maintenance, the power aware scheduler feature was removed
altogther in the 3.5 linux kernel (linux kernel commit:
8e7fbcbc22c12414bcc9dfdd683637f58fb32759).
According to the README file, we currently support kernels that have the
updated power savings level (>= 2.6.38). Therefore, this patch updates
the target value to "2" and conditionally omits adding the tunable for
kernel versions that do not support the feature (>= 3.5).
Nanley Chery (1):
tunable: update sched_mc_power_savings target value
src/tuning/tuning.cpp | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--
2.0.4
11:28 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
Starting in kernel 2.6.29, the highest power savings level increased to "2".
However, in kernel 3.5, the sched power savings feature was removed altogether.
Signed-off-by: Nanley Chery <nanleychery(a)gmail.com>
---
src/tuning/tuning.cpp | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/tuning/tuning.cpp b/src/tuning/tuning.cpp
index 6367a20..ea1905b 100644
--- a/src/tuning/tuning.cpp
+++ b/src/tuning/tuning.cpp
@@ -28,6 +28,7 @@
#include <stdio.h>
#include <string.h>
#include <ncurses.h>
+#include <linux/version.h>
#include "tuning.h"
@@ -58,7 +59,9 @@ static void init_tuning(void)
{
add_sysfs_tunable(_("Enable Audio codec power management"),
"/sys/module/snd_hda_intel/parameters/power_save", "1");
add_sysfs_tunable(_("NMI watchdog should be turned off"),
"/proc/sys/kernel/nmi_watchdog", "0");
- add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "1");
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(3,4,0)
+ add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "2");
+#endif
add_sysfs_tunable(_("VM writeback timeout"),
"/proc/sys/vm/dirty_writeback_centisecs", "1500");
add_sata_tunables();
add_usb_tunables();
--
2.0.4
9:49 p.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On (08/13/14 21:28), Nanley Chery wrote:
Starting in kernel 2.6.29, the highest power savings level increased
to "2".
However, in kernel 3.5, the sched power savings feature was removed altogether.
hello,
thanks for reporting,
so, it's been removed 2 years ago (3.5 release date was 21 Jul 2012).
do we need to support it at all?
-ss
Signed-off-by: Nanley Chery <nanleychery(a)gmail.com>
---
src/tuning/tuning.cpp | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/tuning/tuning.cpp b/src/tuning/tuning.cpp
index 6367a20..ea1905b 100644
--- a/src/tuning/tuning.cpp
+++ b/src/tuning/tuning.cpp
@@ -28,6 +28,7 @@
#include <stdio.h>
#include <string.h>
#include <ncurses.h>
+#include <linux/version.h>
#include "tuning.h"
@@ -58,7 +59,9 @@ static void init_tuning(void)
{
add_sysfs_tunable(_("Enable Audio codec power management"),
"/sys/module/snd_hda_intel/parameters/power_save", "1");
add_sysfs_tunable(_("NMI watchdog should be turned off"),
"/proc/sys/kernel/nmi_watchdog", "0");
- add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "1");
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(3,4,0)
+ add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "2");
+#endif
add_sysfs_tunable(_("VM writeback timeout"),
"/proc/sys/vm/dirty_writeback_centisecs", "1500");
add_sata_tunables();
add_usb_tunables();
--
2.0.4
_______________________________________________
PowerTop mailing list
PowerTop(a)lists.01.org
https://lists.01.org/mailman/listinfo/powertop
4:21 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
sergey.senozhatsky(a)gmail.com> wrote:
On (08/13/14 21:28), Nanley Chery wrote:
> Starting in kernel 2.6.29, the highest power savings level increased to
"2".
> However, in kernel 3.5, the sched power savings feature was removed
altogether.
hello,
thanks for reporting,
so, it's been removed 2 years ago (3.5 release date was 21 Jul 2012).
do we need to support it at all?
Hello,
Good question. Our README file indicates linux-kernel >= 2.6.38 to be a
build requirement. Does this mean we support power management features
starting from that kernel? Or does it mean that this is only a build
requirement and we target the latest kernels? It is not clear from the
current documentation.
On a much smaller scope, supporting this feature is essentially free
(maintenance-wise) and would keep some of our end users on older kernels
happy. Btw, I submitted a simpler version 2 of this patch that does not
check for the kernel version.
Thanks,
Nanley
11:10 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
sergey.senozhatsky(a)gmail.com> wrote:
> On (08/13/14 21:28), Nanley Chery wrote:
> > Starting in kernel 2.6.29, the highest power savings level increased
> to
> "2".
> > However, in kernel 3.5, the sched power savings feature was removed
> altogether.
>
> hello,
> thanks for reporting,
>
>
> so, it's been removed 2 years ago (3.5 release date was 21 Jul 2012).
>
> do we need to support it at all?
Hello,
Good question. Our README file indicates linux-kernel >= 2.6.38 to be a
build requirement. Does this mean we support power management features
starting from that kernel? Or does it mean that this is only a build
requirement and we target the latest kernels? It is not clear from the
current documentation.
On a much smaller scope, supporting this feature is essentially free
(maintenance-wise) and would keep some of our end users on older kernels
happy. Btw, I submitted a simpler version 2 of this patch that does not
check for the kernel version.
Thanks,
Nanley
_______________________________________________
PowerTop mailing list
PowerTop(a)lists.01.org
https://lists.01.org/mailman/listinfo/powertop
From PowerTOP 2.0 and up the requirement is to run at least Linux
kernel
2.6.38. If it is not in the supported kernel then PowerTOP does not need
it.
Thank you,
Alexandra.
2:38 p.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On Fri, Aug 22, 2014 at 9:10 PM, Alexandra Yates <
alexandra.yates(a)linux.intel.com> wrote:
> On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
> sergey.senozhatsky(a)gmail.com> wrote:
>
>> On (08/13/14 21:28), Nanley Chery wrote:
>> > Starting in kernel 2.6.29, the highest power savings level increased
>> to
>> "2".
>> > However, in kernel 3.5, the sched power savings feature was removed
>> altogether.
>>
>> hello,
>> thanks for reporting,
>>
>>
>> so, it's been removed 2 years ago (3.5 release date was 21 Jul 2012).
>>
>> do we need to support it at all?
>
>
> Hello,
>
> Good question. Our README file indicates linux-kernel >= 2.6.38 to be a
> build requirement. Does this mean we support power management features
> starting from that kernel? Or does it mean that this is only a build
> requirement and we target the latest kernels? It is not clear from the
> current documentation.
>
> On a much smaller scope, supporting this feature is essentially free
> (maintenance-wise) and would keep some of our end users on older kernels
> happy. Btw, I submitted a simpler version 2 of this patch that does not
> check for the kernel version.
>
> Thanks,
> Nanley
> _______________________________________________
> PowerTop mailing list
> PowerTop(a)lists.01.org
> https://lists.01.org/mailman/listinfo/powertop
>
From PowerTOP 2.0 and up the requirement is to run at least Linux kernel
2.6.38. If it is not in the supported kernel then PowerTOP does not need
it.
Thank you,
Alexandra.
Since we're supporting kernels starting from 2.6.38 (which has this power
management feature itself), please consider this patch which produces the
correct behavior.
Thanks,
Nanley
3:43 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On Fri, Aug 22, 2014 at 9:10 PM, Alexandra Yates <
alexandra.yates(a)linux.intel.com> wrote:
>
> > On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
> > sergey.senozhatsky(a)gmail.com> wrote:
> >
> >> On (08/13/14 21:28), Nanley Chery wrote:
> >> > Starting in kernel 2.6.29, the highest power savings level
> increased
> >> to
> >> "2".
> >> > However, in kernel 3.5, the sched power savings feature was removed
> >> altogether.
> >>
> >> hello,
> >> thanks for reporting,
> >>
> >>
> >> so, it's been removed 2 years ago (3.5 release date was 21 Jul 2012).
> >>
> >> do we need to support it at all?
> >
> >
> > Hello,
> >
> > Good question. Our README file indicates linux-kernel >= 2.6.38 to be
> a
> > build requirement. Does this mean we support power management features
> > starting from that kernel? Or does it mean that this is only a build
> > requirement and we target the latest kernels? It is not clear from the
> > current documentation.
> >
> > On a much smaller scope, supporting this feature is essentially free
> > (maintenance-wise) and would keep some of our end users on older
> kernels
> > happy. Btw, I submitted a simpler version 2 of this patch that does
> not
> > check for the kernel version.
> >
> > Thanks,
> > Nanley
> > _______________________________________________
> > PowerTop mailing list
> > PowerTop(a)lists.01.org
> > https://lists.01.org/mailman/listinfo/powertop
> >
>
> From PowerTOP 2.0 and up the requirement is to run at least Linux kernel
> 2.6.38. If it is not in the supported kernel then PowerTOP does not need
> it.
>
> Thank you,
> Alexandra.
>
Since we're supporting kernels starting from 2.6.38 (which has this power
management feature itself), please consider this patch which produces the
correct behavior.
Thanks,
Nanley
Hi Nanley,
Thank you for your patch. However, since this feature was faced out the
kernel over two years ago it doesn't make sense to add it now to PowerTOP.
I will update the release notes to use a later kernel. Please excuse the
confusion.
Thank you,
Alexandra.
7:16 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
Hi Alexandra,
Since we're going to require a later kernel, I think we should also remove
the line that adds the (currently broken) sysfs_tunable for this feature as
well.
Cheers,
Nanley
On Mon, Sep 29, 2014 at 1:43 PM, Alexandra Yates <
alexandra.yates(a)linux.intel.com> wrote:
> On Fri, Aug 22, 2014 at 9:10 PM, Alexandra Yates <
> alexandra.yates(a)linux.intel.com> wrote:
>
>>
>> > On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
>> > sergey.senozhatsky(a)gmail.com> wrote:
>> >
>> >> On (08/13/14 21:28), Nanley Chery wrote:
>> >> > Starting in kernel 2.6.29, the highest power savings level
>> increased
>> >> to
>> >> "2".
>> >> > However, in kernel 3.5, the sched power savings feature was
removed
>> >> altogether.
>> >>
>> >> hello,
>> >> thanks for reporting,
>> >>
>> >>
>> >> so, it's been removed 2 years ago (3.5 release date was 21 Jul
2012).
>> >>
>> >> do we need to support it at all?
>> >
>> >
>> > Hello,
>> >
>> > Good question. Our README file indicates linux-kernel >= 2.6.38 to be
>> a
>> > build requirement. Does this mean we support power management features
>> > starting from that kernel? Or does it mean that this is only a build
>> > requirement and we target the latest kernels? It is not clear from the
>> > current documentation.
>> >
>> > On a much smaller scope, supporting this feature is essentially free
>> > (maintenance-wise) and would keep some of our end users on older
>> kernels
>> > happy. Btw, I submitted a simpler version 2 of this patch that does
>> not
>> > check for the kernel version.
>> >
>> > Thanks,
>> > Nanley
>> > _______________________________________________
>> > PowerTop mailing list
>> > PowerTop(a)lists.01.org
>> > https://lists.01.org/mailman/listinfo/powertop
>> >
>>
>> From PowerTOP 2.0 and up the requirement is to run at least Linux kernel
>> 2.6.38. If it is not in the supported kernel then PowerTOP does not need
>> it.
>>
>> Thank you,
>> Alexandra.
>>
>
> Since we're supporting kernels starting from 2.6.38 (which has this power
> management feature itself), please consider this patch which produces the
> correct behavior.
>
> Thanks,
> Nanley
>
Hi Nanley,
Thank you for your patch. However, since this feature was faced out the
kernel over two years ago it doesn't make sense to add it now to PowerTOP.
I will update the release notes to use a later kernel. Please excuse the
confusion.
Thank you,
Alexandra.
8:46 a.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
Hi Alexandra,
Since we're going to require a later kernel, I think we should also remove
the line that adds the (currently broken) sysfs_tunable for this feature
as
well.
Cheers,
Nanley
On Mon, Sep 29, 2014 at 1:43 PM, Alexandra Yates <
alexandra.yates(a)linux.intel.com> wrote:
>
> > On Fri, Aug 22, 2014 at 9:10 PM, Alexandra Yates <
> > alexandra.yates(a)linux.intel.com> wrote:
> >
> >>
> >> > On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
> >> > sergey.senozhatsky(a)gmail.com> wrote:
> >> >
> >> >> On (08/13/14 21:28), Nanley Chery wrote:
> >> >> > Starting in kernel 2.6.29, the highest power savings level
> >> increased
> >> >> to
> >> >> "2".
> >> >> > However, in kernel 3.5, the sched power savings feature was
> removed
> >> >> altogether.
> >> >>
> >> >> hello,
> >> >> thanks for reporting,
> >> >>
> >> >>
> >> >> so, it's been removed 2 years ago (3.5 release date was 21 Jul
> 2012).
> >> >>
> >> >> do we need to support it at all?
> >> >
> >> >
> >> > Hello,
> >> >
> >> > Good question. Our README file indicates linux-kernel >= 2.6.38 to
> be
> >> a
> >> > build requirement. Does this mean we support power management
> features
> >> > starting from that kernel? Or does it mean that this is only a
> build
> >> > requirement and we target the latest kernels? It is not clear from
> the
> >> > current documentation.
> >> >
> >> > On a much smaller scope, supporting this feature is essentially
> free
> >> > (maintenance-wise) and would keep some of our end users on older
> >> kernels
> >> > happy. Btw, I submitted a simpler version 2 of this patch that does
> >> not
> >> > check for the kernel version.
> >> >
> >> > Thanks,
> >> > Nanley
> >> > _______________________________________________
> >> > PowerTop mailing list
> >> > PowerTop(a)lists.01.org
> >> > https://lists.01.org/mailman/listinfo/powertop
> >> >
> >>
> >> From PowerTOP 2.0 and up the requirement is to run at least Linux
> kernel
> >> 2.6.38. If it is not in the supported kernel then PowerTOP does not
> need
> >> it.
> >>
> >> Thank you,
> >> Alexandra.
> >>
> >
> > Since we're supporting kernels starting from 2.6.38 (which has this
> power
> > management feature itself), please consider this patch which produces
> the
> > correct behavior.
> >
> > Thanks,
> > Nanley
> >
>
> Hi Nanley,
>
> Thank you for your patch. However, since this feature was faced out the
> kernel over two years ago it doesn't make sense to add it now to
> PowerTOP.
> I will update the release notes to use a later kernel. Please excuse
> the
> confusion.
>
> Thank you,
> Alexandra.
>
>
This makes sense Nanley. Since you have been working on this already, Do
you want to send a patch with this change?
Thank you,
Alexandra.
12:46 p.m.
New subject: [Powertop] [PATCH] tunables: remove Power Aware CPU scheduler support
Due to seemingly poor code maintenance, the power aware scheduler feature was
removed in the 3.5 linux kernel (see linux kernel commit:
8e7fbcbc22c12414bcc9dfdd683637f58fb32759).
Signed-off-by: Nanley Chery <nanleychery(a)gmail.com>
---
src/tuning/tuning.cpp | 1 -
1 file changed, 1 deletion(-)
diff --git a/src/tuning/tuning.cpp b/src/tuning/tuning.cpp
index 7d64cad..78be52f 100644
--- a/src/tuning/tuning.cpp
+++ b/src/tuning/tuning.cpp
@@ -58,7 +58,6 @@ static void init_tuning(void)
{
add_sysfs_tunable(_("Enable Audio codec power management"),
"/sys/module/snd_hda_intel/parameters/power_save", "1");
add_sysfs_tunable(_("NMI watchdog should be turned off"),
"/proc/sys/kernel/nmi_watchdog", "0");
- add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "1");
add_sysfs_tunable(_("VM writeback timeout"),
"/proc/sys/vm/dirty_writeback_centisecs", "1500");
add_sata_tunables();
add_usb_tunables();
--
2.1.0
12:56 p.m.
New subject: [Powertop] [PATCH 1/1] tunable: update sched_mc_power_savings target value
On Tue, Sep 30, 2014 at 6:46 PM, Alexandra Yates <
alexandra.yates(a)linux.intel.com> wrote:
> Hi Alexandra,
>
> Since we're going to require a later kernel, I think we should also
remove
> the line that adds the (currently broken) sysfs_tunable for this feature
> as
> well.
>
> Cheers,
> Nanley
>
> On Mon, Sep 29, 2014 at 1:43 PM, Alexandra Yates <
> alexandra.yates(a)linux.intel.com> wrote:
>
>>
>> > On Fri, Aug 22, 2014 at 9:10 PM, Alexandra Yates <
>> > alexandra.yates(a)linux.intel.com> wrote:
>> >
>> >>
>> >> > On Tue, Aug 19, 2014 at 7:49 AM, Sergey Senozhatsky <
>> >> > sergey.senozhatsky(a)gmail.com> wrote:
>> >> >
>> >> >> On (08/13/14 21:28), Nanley Chery wrote:
>> >> >> > Starting in kernel 2.6.29, the highest power savings
level
>> >> increased
>> >> >> to
>> >> >> "2".
>> >> >> > However, in kernel 3.5, the sched power savings feature
was
>> removed
>> >> >> altogether.
>> >> >>
>> >> >> hello,
>> >> >> thanks for reporting,
>> >> >>
>> >> >>
>> >> >> so, it's been removed 2 years ago (3.5 release date was 21
Jul
>> 2012).
>> >> >>
>> >> >> do we need to support it at all?
>> >> >
>> >> >
>> >> > Hello,
>> >> >
>> >> > Good question. Our README file indicates linux-kernel >= 2.6.38
to
>> be
>> >> a
>> >> > build requirement. Does this mean we support power management
>> features
>> >> > starting from that kernel? Or does it mean that this is only a
>> build
>> >> > requirement and we target the latest kernels? It is not clear
from
>> the
>> >> > current documentation.
>> >> >
>> >> > On a much smaller scope, supporting this feature is essentially
>> free
>> >> > (maintenance-wise) and would keep some of our end users on older
>> >> kernels
>> >> > happy. Btw, I submitted a simpler version 2 of this patch that
does
>> >> not
>> >> > check for the kernel version.
>> >> >
>> >> > Thanks,
>> >> > Nanley
>> >> > _______________________________________________
>> >> > PowerTop mailing list
>> >> > PowerTop(a)lists.01.org
>> >> > https://lists.01.org/mailman/listinfo/powertop
>> >> >
>> >>
>> >> From PowerTOP 2.0 and up the requirement is to run at least Linux
>> kernel
>> >> 2.6.38. If it is not in the supported kernel then PowerTOP does not
>> need
>> >> it.
>> >>
>> >> Thank you,
>> >> Alexandra.
>> >>
>> >
>> > Since we're supporting kernels starting from 2.6.38 (which has this
>> power
>> > management feature itself), please consider this patch which produces
>> the
>> > correct behavior.
>> >
>> > Thanks,
>> > Nanley
>> >
>>
>> Hi Nanley,
>>
>> Thank you for your patch. However, since this feature was faced out the
>> kernel over two years ago it doesn't make sense to add it now to
>> PowerTOP.
>> I will update the release notes to use a later kernel. Please excuse
>> the
>> confusion.
>>
>> Thank you,
>> Alexandra.
>>
>>
>
This makes sense Nanley. Since you have been working on this already, Do
you want to send a patch with this change?
Sure, I just sent a patch with the change.
Cheers,
Nanley
4:04 a.m.
New subject: [Powertop] [PATCH v2 0/1] Update target value of Power Aware CPU scheduler tunable
Removed the check for the kernel version. add_sysfs_tunable() actually
doesn't create the tunable if the sysfs file doesn't exist. This should
be the case for kernel versions after 3.4, so the problem will be
handled gracefully.
Also word-wrapped the commit to 72 columns.
Nanley Chery (1):
tunable: update sched_mc_power_savings target val
src/tuning/tuning.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--
2.0.4
4:04 a.m.
New subject: [Powertop] [PATCH v2 1/1] tunable: update sched_mc_power_savings target val
Starting in kernel 2.6.29, the highest power savings level increased
to "2". It should be noted that the sched power savings feature was
removed altogether in kernel 3.5.
Signed-off-by: Nanley Chery <nanleychery(a)gmail.com>
---
src/tuning/tuning.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/tuning/tuning.cpp b/src/tuning/tuning.cpp
index 6367a20..90e74d0 100644
--- a/src/tuning/tuning.cpp
+++ b/src/tuning/tuning.cpp
@@ -58,7 +58,7 @@ static void init_tuning(void)
{
add_sysfs_tunable(_("Enable Audio codec power management"),
"/sys/module/snd_hda_intel/parameters/power_save", "1");
add_sysfs_tunable(_("NMI watchdog should be turned off"),
"/proc/sys/kernel/nmi_watchdog", "0");
- add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "1");
+ add_sysfs_tunable(_("Power Aware CPU scheduler"),
"/sys/devices/system/cpu/sched_mc_power_savings", "2");
add_sysfs_tunable(_("VM writeback timeout"),
"/proc/sys/vm/dirty_writeback_centisecs", "1500");
add_sata_tunables();
add_usb_tunables();
--
2.0.4
2909
days inactive
2957
days old
12 comments
3 participants
participants (3)
-
Alexandra Yates -
Nanley Chery -
Sergey Senozhatsky