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

From: Ashay Jaiswal
Date: Tue Feb 06 2024 - 12:08:34 EST




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
>>
>>> 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