v4.18-rc1 on droid 4: very bad CPU performance

v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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Hi!

V4.18 is slower than it should be.

user@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@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?

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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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Tony Lindgren]

* Pavel Machek <pavel@ucw.cz> [180621 12:18]:
> Hi!
> 
> V4.18 is slower than it should be.
> 
> user@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@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?

Regards,

Tony

Re: v4.18-rc1 on droid 4: very bad CPU performance

[Tony Lindgren]

* Tony Lindgren <tony@atomide.com> [180622 07:22]:
> * Pavel Machek <pavel@ucw.cz> [180621 12:18]:
> > Hi!
> > 
> > V4.18 is slower than it should be.
> > 
> > user@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@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.

Regards,

Tony

Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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Hi!

> > > V4.18 is slower than it should be.
> > > 
> > > user@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@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


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

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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Tony Lindgren]

* Pavel Machek <pavel@ucw.cz> [180625 09:52]:
> Hi!
> 
> > > > V4.18 is slower than it should be.
> > > > 
> > > > user@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@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.

Regards,

Tony

Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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On Mon 2018-06-25 23:16:04, Tony Lindgren wrote:
> * Pavel Machek <pavel@ucw.cz> [180625 09:52]:
> > Hi!
> > 
> > > > > V4.18 is slower than it should be.
> > > > > 
> > > > > user@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@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@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@devuan:~$ sudo cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@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@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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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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On Mon 2018-06-25 23:16:04, Tony Lindgren wrote:
> * Pavel Machek <pavel@ucw.cz> [180625 09:52]:
> > Hi!
> > 
> > > > > V4.18 is slower than it should be.
> > > > > 
> > > > > user@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@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.

Ok, so I was able to create .config where bzip2 takes 12 seconds, on
v4.18...

In my normal config, it takes between 20 seconds and minute. Numbers
seem to be stable between boots.

In "fast" config:
processor  : 1
model name : ARMv7 Processor rev 3 (v7l)
BogoMIPS   : 2393.70
Features   : half thumb fastmult vfp edsp thumbee neon vfpv3 tls
vfpd32
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	  : 0x1
CPU part	  : 0xc09
CPU revision	  : 3

12 to 20 seconds is .. pretty significant slowdown. Is it possible
that "fast" config misses errata workaround with impact this
significant?

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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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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On Fri 2018-06-22 00:49:36, Tony Lindgren wrote:
> * Tony Lindgren <tony@atomide.com> [180622 07:22]:
> > * Pavel Machek <pavel@ucw.cz> [180621 12:18]:
> > > Hi!
> > > 
> > > V4.18 is slower than it should be.
> > > 
> > > user@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@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.

Okay, so I know what was wrong with my config. I had l2cache disabled
-- and this solved it:

+CONFIG_OUTER_CACHE=y
+CONFIG_OUTER_CACHE_SYNC=y
+CONFIG_CACHE_L2X0=y
+CONFIG_PL310_ERRATA_588369=y
+CONFIG_PL310_ERRATA_727915=y
+CONFIG_PL310_ERRATA_753970=y
+CONFIG_PL310_ERRATA_769419=y

Now I'm at 12 seconds.

user@devuan:~$ time cat /dev/urandom | head -c 10000000 |  bzip2 -9 - | wc -c
10043993
11.41user 0.44system 11.63 (0m11.637s) elapsed 101.97%CPU
user@devuan:~$ uname -a
Linux devuan 4.18.0-rc2-88315-g3452793-dirty #756 SMP Wed Jun 27 22:16:59 CEST 2018 armv7l GNU/Linux
user@devuan:~$

I was about to add "facepalm" emoji here, as disabling l2 cache is
major mistake. OTOH if you also see 20 seconds, then either there is
another problem, or you need to enable l2 cache, too (and I don't have
to feel too bad for misconfiguring it).

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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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Tony Lindgren]

* Pavel Machek <pavel@ucw.cz> [180627 21:01]:
> On Fri 2018-06-22 00:49:36, Tony Lindgren wrote:
> > * Tony Lindgren <tony@atomide.com> [180622 07:22]:
> > > * Pavel Machek <pavel@ucw.cz> [180621 12:18]:
> > > > Hi!
> > > > 
> > > > V4.18 is slower than it should be.
> > > > 
> > > > user@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@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.
> 
> Okay, so I know what was wrong with my config. I had l2cache disabled
> -- and this solved it:
> 
> +CONFIG_OUTER_CACHE=y
> +CONFIG_OUTER_CACHE_SYNC=y
> +CONFIG_CACHE_L2X0=y
> +CONFIG_PL310_ERRATA_588369=y
> +CONFIG_PL310_ERRATA_727915=y

We have these in omap2plus_defconfig.

> +CONFIG_PL310_ERRATA_753970=y
> +CONFIG_PL310_ERRATA_769419=y

These two should not be needed from what I recall. Have not
checked against processor revisions or errata though. But
I verified that my duovero time stays at 21 seconds also
with these enabled. It seems to run at 600MHz so it's slower
compared to droid4.

> Now I'm at 12 seconds.
> 
> user@devuan:~$ time cat /dev/urandom | head -c 10000000 |  bzip2 -9 - | wc -c
> 10043993
> 11.41user 0.44system 11.63 (0m11.637s) elapsed 101.97%CPU
> user@devuan:~$ uname -a
> Linux devuan 4.18.0-rc2-88315-g3452793-dirty #756 SMP Wed Jun 27 22:16:59 CEST 2018 armv7l GNU/Linux
> user@devuan:~$
> 
> I was about to add "facepalm" emoji here, as disabling l2 cache is
> major mistake. OTOH if you also see 20 seconds, then either there is
> another problem, or you need to enable l2 cache, too (and I don't have
> to feel too bad for misconfiguring it).

OK. I checked and duovero runs only at 600MHz. I can only
get down to 19 seconds with omap2plus_defconfig if I disable
CONFIG_CPU_FREQ so the max speed is maintained from bootloader.
Otherwise it runs at most at 1GHz, I think any higher speeds
need smartreflex and voltage scaling working which we don't
have in the mainline kernel. Not sure what happens with higher
speeds with mainline kernel or if they are unsafe in the long
run.

Anyways, care to post your .config somewhere so I can see what
the numbers are for me with it?

Regards,

Tony

Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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Hi!

> > I was about to add "facepalm" emoji here, as disabling l2 cache is
> > major mistake. OTOH if you also see 20 seconds, then either there is
> > another problem, or you need to enable l2 cache, too (and I don't have
> > to feel too bad for misconfiguring it).
> 
> OK. I checked and duovero runs only at 600MHz. I can only
> get down to 19 seconds with omap2plus_defconfig if I disable
> CONFIG_CPU_FREQ so the max speed is maintained from bootloader.
> Otherwise it runs at most at 1GHz, I think any higher speeds
> need smartreflex and voltage scaling working which we don't
> have in the mainline kernel. Not sure what happens with higher
> speeds with mainline kernel or if they are unsafe in the long
> run.
> 
> Anyways, care to post your .config somewhere so I can see what
> the numbers are for me with it?

I'm attaching config I'm using for v4.18. In current boot, bzip2 takes
16 seconds.

user@devuan:~$ time cat /dev/urandom | head -c 10000000 |  sudo nice
-n -19 bzip2 -9 - | wc -c
10044705
15.68user 0.53system 15.93 (0m15.931s) elapsed 101.82%CPU

I guess I should go back to v4.17 to get 12 seconds..?!

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

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Re: v4.18-rc1 on droid 4: very bad CPU performance

[Pavel Machek]

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Hi!

> OK. I checked and duovero runs only at 600MHz. I can only
> get down to 19 seconds with omap2plus_defconfig if I disable
> CONFIG_CPU_FREQ so the max speed is maintained from bootloader.
> Otherwise it runs at most at 1GHz, I think any higher speeds
> need smartreflex and voltage scaling working which we don't
> have in the mainline kernel. Not sure what happens with higher
> speeds with mainline kernel or if they are unsafe in the long
> run.
> 
> Anyways, care to post your .config somewhere so I can see what
> the numbers are for me with it?

After reboot (same config as in previous mail), before x / ofono /
unicsy_demo /... were started:

user@devuan:~$ uname -a
Linux devuan 4.18.0-rc3-88788-g528947b #758 SMP Wed Jul 4 10:05:21
CEST 2018 armv7l GNU/Linux
user@devuan:~$ time cat /dev/urandom | head -c 10000000 |  bzip2 -9 -
| wc -c
10044041
11.50user 0.37system 11.57 (0m11.570s) elapsed 102.63%CPU
user@devuan:~$

droid 4.

								Pavel

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

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