Re: android-kernel memory reclaim x20 boost?

From: Arve Hjønnevåg
Date: Wed Aug 18 2010 - 21:02:06 EST


On Wed, Aug 18, 2010 at 5:54 PM, Minchan Kim <minchan.kim@xxxxxxxxx> wrote:
> On Thu, Aug 19, 2010 at 12:26 AM, Alejandro Riveira Fernández
> <ariveira@xxxxxxxxx> wrote:
>> El Thu, 19 Aug 2010 00:18:57 +0900
>> Minchan Kim <minchan.kim@xxxxxxxxx> escribió:
>>
>>> Hello Android forks,
>> [ ... ]
>>>
>>> I saw the advertisement phrase in this[1].
>>>
>>> "Kernel Memory Management Boost: Improved memory reclaim by up to 20x,
>>> which results in faster app switching and smoother performance
>>> on memory-constrained devices."
>>>
>>> But I can't find any code for it in android kernel git tree.
>>
>>  Maybe the enhancements are on the Dalvik VM (shooting in the dark here)
>
> Thanks.
> Android guys! Could you confirm this?
>

It is more likely referring to this change:

Author: San Mehat <san@xxxxxxxxxx>
Date: Wed May 5 11:38:42 2010 -0700

staging: android: lowmemkiller: Substantially reduce overhead during reclaim

This patch optimizes lowmemkiller to not do any work when it has
an outstanding
kill-request. This greatly reduces the pressure on the task_list lock
(improving interactivity), as well as improving the vmscan performance
when under heavy memory pressure (by up to 20x in tests).

Note: For this enhancement to work, you need CONFIG_PROFILING

Signed-off-by: San Mehat <san@xxxxxxxxxx>


--
Arve Hjønnevåg
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/