Re: [gentoo-user] Puzzled with duration of chromium emerge under profile 17.0

2017-12-06 Thread Mick 
On Wednesday, 6 December 2017 20:13:50 GMT Alan McKinnon wrote:
> On 06/12/2017 21:10, Mick wrote:
> > I discovered that building Chromium with gcc-6.4.0 is taking an
> > inordinately> 
> > longer time on a laptop with 1st gen i7 and 4G of RAM, e.g.:
[snip...]

> Pure gut feel and intuition and nothing else leads me to look in two places:
> 
> You use -march=native on the i7 so I assume the same on the Core2? Those
> are rather different processors, and google is fond of optimizing deeply
> for specific cases (common to all browsers I think). You'd have to ask a
> chromium hacker but I'd say the odds are good there are serious
> optimizations for i7 that stress your compiler out muchly.

Yes, I run -march=native on both.

> Add to that your i7 is RAM-constrained so you compensate with swap,
> which is easily 50,000 times slower with sucky latency. 

Yes, it's ridiculously slow!  :-(


> When you use a
> disk as RAM, performance tanks. Well, usually it causes a cascade effect
> and stuff blows up, but if it completes it will have done so slowly.
> 
> If you at all can, shove lots more RAM in that i7. These days RAM is
> cheap and it's always by first performance tweak, then SSD.

I know that compiling in RAM would be done in a fraction of the time.  The 
thing is, this is a 8 year old laptop and I am resisting throwing good money 
after bad.  I had a quick look a few months ago and good quality memory will 
cost me around £60.  With the battery shot and the keyboard on its way out, 
I'd rather put the money towards more memory for a newer PC, sometime in the 
next year.  ;-)

-- 
Regards,
Mick

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Re: [gentoo-user] Puzzled with duration of chromium emerge under profile 17.0

2017-12-06 Thread Alan McKinnon 
On 06/12/2017 21:10, Mick wrote:
> I discovered that building Chromium with gcc-6.4.0 is taking an inordinately 
> longer time on a laptop with 1st gen i7 and 4G of RAM, e.g.: 
> 
>  Wed Sep 27 17:36:53 2017 >>> www-client/chromium-61.0.3163.100
>merge time: 6 hours, 40 minutes and 50 seconds.
> 
>  Thu Nov  9 17:44:58 2017 >>> www-client/chromium-62.0.3202.89
>merge time: 8 hours, 12 minutes and 30 seconds.
> 
> -->switch to gcc-6.4.0
> 
>  Mon Dec  4 11:39:36 2017 >>> www-client/chromium-62.0.3202.89
>merge time: 20 hours, 2 minutes and 4 seconds.
> 
>  Wed Dec  6 18:41:13 2017 >>> www-client/chromium-62.0.3202.94
>merge time: 22 hours, 47 minutes and 35 seconds.
> 
> 
> but not so on another older and lesser Intel(R) Core(TM)2 Duo CPU P7550  @ 
> 2.26GHz, also with 4G RAM:
> 
>  Wed Sep 27 22:25:32 2017 >>> www-client/chromium-61.0.3163.100
>merge time: 11 hours, 46 minutes and 18 seconds.
> 
>  Thu Nov  9 22:09:59 2017 >>> www-client/chromium-62.0.3202.89
>merge time: 13 hours, 16 minutes and 41 seconds.
> 
> -->switch to gcc-6.4.0
> 
>  Sat Dec  2 21:00:59 2017 >>> www-client/chromium-62.0.3202.89
>merge time: 15 hours, 35 minutes and 50 seconds.
> 
>  Mon Dec  4 03:44:12 2017 >>> www-client/chromium-62.0.3202.94
>merge time: 15 hours, 40 minutes and 18 seconds.
> 
> 
> Any idea why this is happening?  I attach emerge info of the i7 in case you 
> can spot something which may be causing this exponential increase in emerge 
> times.  BTW, on the i7 I had to increase swap because the 4,200,960 KiB swap 
> partition was not enough to complete the compilation of version 62.0.3202.89, 
> even after I shut down all applications and exited X.  O_O
> 


Pure gut feel and intuition and nothing else leads me to look in two places:

You use -march=native on the i7 so I assume the same on the Core2? Those
are rather different processors, and google is fond of optimizing deeply
for specific cases (common to all browsers I think). You'd have to ask a
chromium hacker but I'd say the odds are good there are serious
optimizations for i7 that stress your compiler out muchly.

Add to that your i7 is RAM-constrained so you compensate with swap,
which is easily 50,000 times slower with sucky latency. When you use a
disk as RAM, performance tanks. Well, usually it causes a cascade effect
and stuff blows up, but if it completes it will have done so slowly.

If you at all can, shove lots more RAM in that i7. These days RAM is
cheap and it's always by first performance tweak, then SSD.

-- 
Alan McKinnon
alan.mckin...@gmail.com

[gentoo-user] Puzzled with duration of chromium emerge under profile 17.0

2017-12-06 Thread Mick 
I discovered that building Chromium with gcc-6.4.0 is taking an inordinately 
longer time on a laptop with 1st gen i7 and 4G of RAM, e.g.: 

 Wed Sep 27 17:36:53 2017 >>> www-client/chromium-61.0.3163.100
   merge time: 6 hours, 40 minutes and 50 seconds.

 Thu Nov  9 17:44:58 2017 >>> www-client/chromium-62.0.3202.89
   merge time: 8 hours, 12 minutes and 30 seconds.

-->switch to gcc-6.4.0

 Mon Dec  4 11:39:36 2017 >>> www-client/chromium-62.0.3202.89
   merge time: 20 hours, 2 minutes and 4 seconds.

 Wed Dec  6 18:41:13 2017 >>> www-client/chromium-62.0.3202.94
   merge time: 22 hours, 47 minutes and 35 seconds.


but not so on another older and lesser Intel(R) Core(TM)2 Duo CPU P7550  @ 
2.26GHz, also with 4G RAM:

 Wed Sep 27 22:25:32 2017 >>> www-client/chromium-61.0.3163.100
   merge time: 11 hours, 46 minutes and 18 seconds.

 Thu Nov  9 22:09:59 2017 >>> www-client/chromium-62.0.3202.89
   merge time: 13 hours, 16 minutes and 41 seconds.

-->switch to gcc-6.4.0

 Sat Dec  2 21:00:59 2017 >>> www-client/chromium-62.0.3202.89
   merge time: 15 hours, 35 minutes and 50 seconds.

 Mon Dec  4 03:44:12 2017 >>> www-client/chromium-62.0.3202.94
   merge time: 15 hours, 40 minutes and 18 seconds.


Any idea why this is happening?  I attach emerge info of the i7 in case you 
can spot something which may be causing this exponential increase in emerge 
times.  BTW, on the i7 I had to increase swap because the 4,200,960 KiB swap 
partition was not enough to complete the compilation of version 62.0.3202.89, 
even after I shut down all applications and exited X.  O_O

-- 
Regards,
Mick~ $ emerge --info www-client/chromium
Portage 2.3.13 (python 3.5.4-final-0, default/linux/amd64/17.0/desktop/plasma, g
cc-6.4.0, glibc-2.25-r9, 4.12.12-gentoo x86_64)
=
 System Settings
=
System uname: Linux-4.12.12-gentoo-x86_64-Intel-R-_Core-TM-_i7_CPU_Q_720_@_1.60G
Hz-with-gentoo-2.4.1
KiB Mem: 4032296 total,   2050332 free
KiB Swap:4200960 total,   4200960 free
Timestamp of repository gentoo: Wed, 06 Dec 2017 18:15:01 +
Head commit of repository gentoo: f2378f105da3bbdc56fe40323b97dd31044b8dcc
sh bash 4.3_p48-r1
ld GNU ld (Gentoo 2.29.1 p3) 2.29.1
app-shells/bash:  4.3_p48-r1::gentoo
dev-lang/perl:5.24.3::gentoo
dev-lang/python:  2.7.14::gentoo, 3.5.4::gentoo
dev-util/cmake:   3.8.2::gentoo
dev-util/pkgconfig:   0.29.2::gentoo
sys-apps/baselayout:  2.4.1-r2::gentoo
sys-apps/openrc:  0.34.11::gentoo
sys-apps/sandbox: 2.10-r4::gentoo
sys-devel/autoconf:   2.13::gentoo, 2.69::gentoo
sys-devel/automake:   1.15.1-r1::gentoo
sys-devel/binutils:   2.29.1-r1::gentoo
sys-devel/gcc:6.4.0::gentoo
sys-devel/gcc-config: 1.8-r1::gentoo
sys-devel/libtool:2.4.6-r3::gentoo
sys-devel/make:   4.2.1::gentoo
sys-kernel/linux-headers: 4.4::gentoo (virtual/os-headers)
sys-libs/glibc:   2.25-r9::gentoo
Repositories:

gentoo
location: /usr/portage
sync-type: rsync
sync-uri: rsync://10.10.10.2/gentoo-portage
priority: -1000
sync-rsync-extra-opts: --exclude-from=/etc/portage/rsync_excludes

bar
location: /var/lib/layman/bar
masters: gentoo
priority: 50

brother-overlay
location: /var/lib/layman/brother-overlay
masters: gentoo
priority: 50

psix-overlay
location: /var/lib/layman/psix-overlay
masters: gentoo
priority: 50

local
location: /usr/local/portage
masters: gentoo
priority: 100

Installed sets: @enlightenment
ACCEPT_KEYWORDS="amd64"
ACCEPT_LICENSE="* -@EULA"
CBUILD="x86_64-pc-linux-gnu"
CFLAGS="-march=native -O2 -pipe"
CHOST="x86_64-pc-linux-gnu"
CONFIG_PROTECT="/etc /usr/lib64/libreoffice/program/sofficerc /usr/share/config
/usr/share/gnupg/qualified.txt"
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/dconf /etc/env.d /etc/fonts/
fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /et
c/terminfo"
CXXFLAGS="-march=native -O2 -pipe"
DISTDIR="/usr/portage/distfiles"
EMERGE_DEFAULT_OPTS="--quiet-build=n"
FCFLAGS="-O2 -pipe"
FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild
-locks fail-clean fixlafiles merge-sync multilib-strict network-sandbox news par
allel-fetch preserve-libs protect-owned sandbox sfperms splitdebug strict unknow
n-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox user
sync xattr"
FFLAGS="-O2 -pipe"
GENTOO_MIRRORS="http://10.10.10.2:1024/ http://mirror.qubenet.net/mirror/gentoo/
 rsync://rsync.mirrorservice.org/distfiles.gentoo.org/ http://ftp.snt.utwente.nl
/pub/os/linux/gentoo ftp://ftp.snt.utwente.nl/pub/os/linux/gentoo http://www.mir
rorservice.org/sites/distfiles.gentoo.org/"
LANG="en_GB.UTF-8"
LDFLAGS="-Wl,-O1 -Wl,--as-needed"