Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 23 Nov 2019 14:26:17 -0800
From:      Mark Millard <marklmi@yahoo.com>
To:        freebsd-arm@freebsd.org
Subject:   head -r355027 on Rock64: CPU staying at 600 MHz? (based on ArchLinuxARM benchmark comparison)
Message-ID:  <BEB4FC89-C9BE-4FF3-8830-BB2B4B732B29@yahoo.com>
References:  <BEB4FC89-C9BE-4FF3-8830-BB2B4B732B29.ref@yahoo.com>

next in thread | previous in thread | raw e-mail | index | archive | help
I ran my C++ variation on the old HINT serial/threads benchmark
on ArchLinuxARM (5.3.12 kernel) and FreeBSD -r355027 and got
a surprise for the CPU/memory-cache dominated range.

The benchmark explores from small problems dependent primarily
on CPU speed (and memory cache speed) to sizes/patterns dominated
by RAM speed (the access pattern makes caches far less effective).
(I do not normally use it to explore sizes that would involve
paging and have not done so here.)

The RAM-speed dominated part is ball park similar, as expected.

BUT: For the CPU/cache-speed dominated part FreeBSD is near a
factor of 2 slower than for ArchLinuxARM.

My guess is that the FreeBSD CPU frequency is staying at 600 MHz
instead of going to the 1200MHz or 1296MHz that is listed as
possible:

dev.cpufreq_dt.3.freq_settings: 408/-1 600/-1 816/-1 1008/-1 1200/-1 1296/-1
dev.cpufreq_dt.3.%parent: cpu3
dev.cpufreq_dt.3.%pnpinfo: 
dev.cpufreq_dt.3.%location: 
dev.cpufreq_dt.3.%driver: cpufreq_dt
dev.cpufreq_dt.3.%desc: Generic cpufreq driver
dev.cpufreq_dt.2.freq_settings: 408/-1 600/-1 816/-1 1008/-1 1200/-1 1296/-1
dev.cpufreq_dt.2.%parent: cpu2
dev.cpufreq_dt.2.%pnpinfo: 
dev.cpufreq_dt.2.%location: 
dev.cpufreq_dt.2.%driver: cpufreq_dt
dev.cpufreq_dt.2.%desc: Generic cpufreq driver
dev.cpufreq_dt.1.freq_settings: 408/-1 600/-1 816/-1 1008/-1 1200/-1 1296/-1
dev.cpufreq_dt.1.%parent: cpu1
dev.cpufreq_dt.1.%pnpinfo: 
dev.cpufreq_dt.1.%location: 
dev.cpufreq_dt.1.%driver: cpufreq_dt
dev.cpufreq_dt.1.%desc: Generic cpufreq driver
dev.cpufreq_dt.0.freq_settings: 408/-1 600/-1 816/-1 1008/-1 1200/-1 1296/-1
dev.cpufreq_dt.0.%parent: cpu0
dev.cpufreq_dt.0.%pnpinfo: 
dev.cpufreq_dt.0.%location: 
dev.cpufreq_dt.0.%driver: cpufreq_dt
dev.cpufreq_dt.0.%desc: Generic cpufreq driver
dev.cpufreq_dt.%parent: 
dev.cpu.0.freq_levels: 1296/-1 1200/-1 1008/-1 816/-1 600/-1 408/-1
dev.cpu.0.freq: 600

(The above was not from during a benchmark run: just showing the
default and the alternatives listed.)

Is the reversal of ordering of freq_settings vs. freq_levels also
interesting?

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?BEB4FC89-C9BE-4FF3-8830-BB2B4B732B29>