Messages in this thread | | | Date | Mon, 8 Nov 2021 09:22:42 -0600 | Subject | Re: [PATCH v3 0/5] Refactor thermal pressure update to avoid code duplication | From | Steev Klimaszewski <> |
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> 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 :
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
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