Messages in this thread | | | Subject | Re: [PATCH v3 0/5] Refactor thermal pressure update to avoid code duplication | From | Thara Gopinath <> | Date | Mon, 8 Nov 2021 16:31:44 -0500 |
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On 11/8/21 10:22 AM, Steev Klimaszewski wrote: > >> Hi Steev, >> >> So this depends on the cpufreq governor you are using. By-default arm >> systems have sched-util governor enabled. This means you will scale up >> to boost depending on cpu load and not always. If you want to ensure >> you are always hitting boost frequency, you should enable performance >> governor for cpufreq and try. >> >> Also since the defconfig has by default CPU_FREQ_STAT enabled, you >> should be able to get statistics out of cpufreq to see the time spent >> by a cpu in each frequency. I think cpufreq-info -s should give you >> this info. If not, you can explicitly get it for each cpu from >> >> cat /sys/devices/system/cpu/cpu<X>/cpufreq/stats/time_in_state >> >> Regarding temperature, if you have applied all the patches in the >> sdm845 LMh series and have LMh enabled, cpu throttling starts around >> 95 degree C. >> > Hi Thara, > > Indeed, I ended up finding the time_in_state when I was doing more > digging after my last mail. I do have the sdm845 LMh series and LMh > enabled, however I don't think I've ever seen my system go above 90C here. > > So a quick look, and... we are simply almost never getting the 2.95GHz > at all, regardless of workload. I saw Lukasz response as well about the > math possibly being wrong, but I haven't had a chance. > > Regarding the time in state - I went with policy4 instead of per cpu > (for brevity sake) and it's here: > > c630:~$ cat /sys/devices/system/cpu/cpufreq/policy4/stats/time_in_state > 825600 225037 > 902400 92 > 979200 205 > 1056000 96 > 1209600 902 > 1286400 386 > 1363200 396 > 1459200 217 > 1536000 101 > 1612800 75 > 1689600 95 > 1766400 130 > 1843200 255 > 1920000 318 > 1996800 92 > 2092800 87 > 2169600 66 > 2246400 60 > 2323200 58 > 2400000 54 > 2476800 47 > 2553600 50 > 2649600 69 > 2745600 58 > 2841600 54619 > 2956800 5 > > So we spend *very* little time in 2.96GHz and this is after almost 14 > hours of uptime on the C630. By comparison, on a Pinebook Pro where > I've added in 2GHz as a boost frequency :
Hi Steev,
IIUC, PineBook Pro has Rockchip RK3399 which has 2 Cortex A-72 and 4 Cortex A-52 where as C630 has Qualcomm sdm845 which has 4 Cortex A-75 and 4 Cortex A-55. Task placements and subsequently cpu load will be different for both the platforms. With the same workload, I will expect Rockchip to system to be more loaded than sdm845. Having said that, what cpu-freq governor are you using on both the systems.
> > pinebook-pro:~$ cat > /sys/devices/system/cpu/cpufreq/policy4/stats/time_in_state > 408000 16084466 > 600000 27212 > 816000 32487 > 1008000 11331 > 1200000 13268 > 1416000 75078 > 1608000 18392 > 1800000 207266 > 2016000 648612 > > With the Pinebook Pro, which doesn't even come close to getting to 95C, > we spend a lot more time in 2GHz. > > -- steev >
-- Warm Regards Thara (She/Her/Hers)
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