Add memory pressure monitor for Linux.

Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further refinements will be made to improve it.

BUG=463606
Committed: https://crrev.com/2abebe8ecc67ba5a27a6a371f4f9186fbab2522a
Cr-Commit-Position: refs/heads/master@{#370762}

[Georges Khalil, 2016-01-20 17:58:50]

Description was changed from

==========
Add linux memory pressure.


Add memory pressure monitor for Linux.

BUG=

patch from issue 1571473002 at patchset 40001
(http://crrev.com/1571473002#ps40001)
==========

to

==========
Add memory pressure monitor for Linux.

BUG=
==========

[Georges Khalil, 2016-01-20 18:36:23]

Description was changed from

==========
Add memory pressure monitor for Linux.

BUG=
==========

to

==========
Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further
refinements will be made to improve it.

BUG=463606
==========

[Georges Khalil, 2016-01-20 18:36:23]

georgesak@chromium.org changed reviewers:
+ chrisha@chromium.org

[Georges Khalil, 2016-01-20 18:36:28]

PTAL.

[chrisha, 2016-01-20 20:55:43]

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
File components/memory_pressure/direct_memory_pressure_calculator_linux.cc
(right):

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:14: static
const int kKBperMB = 1024;
pedantic nit: kKiBperMiB

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:18: //
Threshholds at which we consider the system being under moderate/critical
Thresholds*

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:21: const
int DirectMemoryPressureCalculator::kDefaultCriticalThresholdPc = 90;
I imagine Pc = Percent? Just spell it out already, or at least mention the units
in the comment above.

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
File components/memory_pressure/direct_memory_pressure_calculator_linux.h
(left):

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.h:16: #if
defined(MEMORY_PRESSURE_IS_POLLING)
The linux calculator is also polling, so this keep those ifdefs as well?

[Georges Khalil, 2016-01-21 14:47:44]

PTAL.

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
File components/memory_pressure/direct_memory_pressure_calculator_linux.cc
(right):

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:14: static
const int kKBperMB = 1024;
On 2016/01/20 20:55:43, chrisha wrote:
> pedantic nit: kKiBperMiB

Done.

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:18: //
Threshholds at which we consider the system being under moderate/critical
On 2016/01/20 20:55:43, chrisha wrote:
> Thresholds*

Done.

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.cc:21: const
int DirectMemoryPressureCalculator::kDefaultCriticalThresholdPc = 90;
On 2016/01/20 20:55:43, chrisha wrote:
> I imagine Pc = Percent? Just spell it out already, or at least mention the
units
> in the comment above.

Done.

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
File components/memory_pressure/direct_memory_pressure_calculator_linux.h
(left):

https://codereview.chromium.org/1603413003/diff/1/components/memory_pressure/...
components/memory_pressure/direct_memory_pressure_calculator_linux.h:16: #if
defined(MEMORY_PRESSURE_IS_POLLING)
On 2016/01/20 20:55:43, chrisha wrote:
> The linux calculator is also polling, so this keep those ifdefs as well?

That ifdef is useless, it will always be true, since we know that the linux
implementation is polling.

[chrisha, 2016-01-21 18:33:12]

lgtm!

[Georges Khalil, 2016-01-21 18:33:35]

The CQ bit was checked by georgesak@chromium.org

[commit-bot: I haz the power, 2016-01-21 18:34:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1603413003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1603413003/20001

[commit-bot: I haz the power, 2016-01-21 20:00:34]

Description was changed from

==========
Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further
refinements will be made to improve it.

BUG=463606
==========

to

==========
Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further
refinements will be made to improve it.

BUG=463606
==========

[commit-bot: I haz the power, 2016-01-21 20:00:34]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-01-21 20:01:25]

Description was changed from

==========
Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further
refinements will be made to improve it.

BUG=463606
==========

to

==========
Add memory pressure monitor for Linux.

Note that this is a very basic algorithm to get us jump started. Further
refinements will be made to improve it.

BUG=463606

Committed: https://crrev.com/2abebe8ecc67ba5a27a6a371f4f9186fbab2522a
Cr-Commit-Position: refs/heads/master@{#370762}
==========

[commit-bot: I haz the power, 2016-01-21 20:01:26]

Patchset 2 (id:??) landed as
https://crrev.com/2abebe8ecc67ba5a27a6a371f4f9186fbab2522a
Cr-Commit-Position: refs/heads/master@{#370762}