Re: [PATCH v2 8/8] sched/pelt: Introduce PELT multiplier

From: Ashay Jaiswal
Date: Fri Apr 12 2024 - 06:08:01 EST


On 2/6/2024 10:37 PM, Ashay Jaiswal wrote:
>
>
> On 1/30/2024 10:58 PM, Vincent Guittot wrote:
>> On Sun, 28 Jan 2024 at 17:22, Ashay Jaiswal <quic_ashayj@xxxxxxxxxxx> wrote:
>>>
>>> Hello Qais Yousef,
>>>
>>> Thank you for your response.
>>>
>>> On 1/21/2024 5:34 AM, Qais Yousef wrote:
>>>> Hi Ashay
>>>>
>>>> On 01/20/24 13:22, Ashay Jaiswal wrote:
>>>>> Hello Qais Yousef,
>>>>>
>>>>> We ran few benchmarks with PELT multiplier patch on a Snapdragon 8Gen2
>>>>> based internal Android device and we are observing significant
>>>>> improvements with PELT8 configuration compared to PELT32.
>>>>>
>>>>> Following are some of the benchmark results with PELT32 and PELT8
>>>>> configuration:
>>>>>
>>>>> +-----------------+---------------+----------------+----------------+
>>>>> | Test case | PELT32 | PELT8 |
>>>>> +-----------------+---------------+----------------+----------------+
>>>>> | | Overall | 711543 | 971275 |
>>>>> | +---------------+----------------+----------------+
>>>>> | | CPU | 193704 | 224378 |
>>>>> | +---------------+----------------+----------------+
>>>>> |ANTUTU V9.3.9 | GPU | 284650 | 424774 |
>>>>> | +---------------+----------------+----------------+
>>>>> | | MEM | 125207 | 160548 |
>>>>> | +---------------+----------------+----------------+
>>>>> | | UX | 107982 | 161575 |
>>>>> +-----------------+---------------+----------------+----------------+
>>>>> | | Single core | 1170 | 1268 |
>>>>> |GeekBench V5.4.4 +---------------+----------------+----------------+
>>>>> | | Multi core | 2530 | 3797 |
>>>>> +-----------------+---------------+----------------+----------------+
>>>>> | | Twitter | >50 Janks | 0 |
>>>>> | SCROLL +---------------+----------------+----------------+
>>>>> | | Contacts | >30 Janks | 0 |
>>>>> +-----------------+---------------+----------------+----------------+
>>>>>
>>>>> Please let us know if you need any support with running any further
>>>>> workloads for PELT32/PELT8 experiments, we can help with running the
>>>>> experiments.
>>>>
>>>> Thanks a lot for the test results. Was this tried with this patch alone or
>>>> the whole series applied?
>>>>
>>> I have only applied patch8(sched/pelt: Introduce PELT multiplier) for the tests.
>>>
>>>> Have you tried to tweak each policy response_time_ms introduced in patch
>>>> 7 instead? With the series applied, boot with PELT8, record the response time
>>>> values for each policy, then boot back again to PELT32 and use those values.
>>>> Does this produce similar results?
>>>>
>>> As the device is based on 5.15 kernel, I will try to pull all the 8 patches
>>> along with the dependency patches on 5.15 and try out the experiments as
>>> suggested.
>>
>> Generally speaking, it would be better to compare with the latest
>> kernel or at least close and which includes new features added since
>> v5.15 (which is more than 2 years old now). I understand that this is
>> not always easy or doable but you could be surprised by the benefit of
>> some features like [0] merged since v5.15
>>
>> [0] https://lore.kernel.org/lkml/249816c9-c2b5-8016-f9ce-dab7b7d384e4@xxxxxxx/
>>
> Thank you Vincent for the suggestion, I will try to get the results on device running
> with most recent kernel and update.
>
> Thanks,
> Ashay Jaiswal

Hello Qais Yousef and Vincent,

Sorry for the delay, setting up internal device on latest kernel is taking more time than anticipated.
We are trying to bring-up latest kernel on the device and will complete the testing with the latest
cpufreq patches as you suggested.

Regarding PELT multiplier patch [1], are we planning to merge it separately or will it be merged
altogether with the cpufreq patches?

[1]: https://lore.kernel.org/all/20231208002342.367117-9-qyousef@xxxxxxxxxxx/

Thanks and Regards,
Ashay Jaiswal

>>>
>>>> You didn't share power numbers which I assume the perf gains are more important
>>>> than the power cost for you.
>>>>
>>> If possible I will try to collect the power number for future test and share the
>>> details.
>>>
>>>>
>>>> Thanks!
>>>>
>>>> --
>>>> Qais Yousef