On Mon 2018-06-25 23:16:04, Tony Lindgren wrote:

* Pavel Machek [off-list ref] [180625 09:52]:

quoted

Hi!

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quoted

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V4.18 is slower than it should be.

user at devuan:~$ time cat /dev/urandom | head -c 10000000 |  bzip2 -9 -
| wc -c
10044291
52.73user 2.40system 61.53 (1m1.534s) elapsed 89.60%CPU
user at devuan:~$ uname -a
Linux devuan 4.18.0-rc1-87964-gfa19934-dirty #743 SMP Sun Jun 17
19:26:37 CEST 2018 armv7l GNU/Linux

That bzip should take 12 seconds, not minute.

Any ideas? Do you see it, too?

I've noticed firefox is super slow.. Git bisect time?

Hmm not happening for me at least on duovero and droid4,
I'm getting about 20s for v4.17 and v4.18-rc1.

Something weird is going on here. My notes say it should be 12
seconds.

It is indeed 20 seconds for v4.17, but it is 12 seconds in v4.14.

v4.14 is:
# CONFIG_CPU_FREQ is not set
CONFIG_CPU_IDLE=y
# CONFIG_CPU_IDLE_GOV_LADDER is not set
CONFIG_CPU_IDLE_GOV_MENU=y
# CONFIG_ARM_CPUIDLE is not set

In v4.18, I have:

CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_ATTR_SET=y
CONFIG_CPU_FREQ_GOV_COMMON=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y

CONFIG_CPU_IDLE=y
CONFIG_CPU_IDLE_GOV_MENU=y
CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED=y

I gave it a quick try here with v4.14 and it was 21 seconds
on 4430 duovero. But this was with omap2plus_defconfig.

Weird. In v4.18 I seen times from 57 seconds to 27 seconds to 20
seconds. It seems to be consistent after boot.

v4.14 is fast... 12 second. v4.15 (all-v4.15 branch) -- no
boot. all-v4.16 -- 15.7 seconds. all-v4.18 with "all" config: time
varies (20, 24, 27, 57 seconds). all-v4.18 with "droid4" config: 20
seconds.

What needs to be done to get cpufreq to work? One of my hypothesis is
that cpu is running at wrong rate. I have it enabled in config, but no
luck:

user at devuan:~$ zcat /proc/config.gz | grep CPU_FREQ
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_ATTR_SET=y
CONFIG_CPU_FREQ_GOV_COMMON=y
CONFIG_CPU_FREQ_STAT=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y
# CONFIG_CPU_FREQ_GOV_SCHEDUTIL is not set
user at devuan:~$ sudo cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq at vger.kernel.org, please.
analyzing CPU 0:
  no or unknown cpufreq driver is active on this CPU
    maximum transition latency: 0.00 ms.
    analyzing CPU 1:
 no or unknown cpufreq driver is active on this CPU
 maximum transition latency: 0.00 ms.
user at devuan:~$

Best regards,

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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