jpetazzo

#!/bin/sh
sudo sh -c 'for CPU in /sys/devices/system/cpu/cpu[0-9]* ; do echo powersave > $CPU/cpufreq/scaling_governor ; done'
sudo sh -c 'for CPU in /sys/devices/system/cpu/cpu[0-9]* ; do echo  800000 > $CPU/cpufreq/scaling_min_freq ; done'
sudo sh -c 'for CPU in /sys/devices/system/cpu/cpu[0-9]* ; do echo 2000000 > $CPU/cpufreq/scaling_setspeed ; done'
sudo sh -c 'for CPU in /sys/devices/system/cpu/cpu[0-9]* ; do echo 2000000 > $CPU/cpufreq/scaling_max_freq ; done'

jpetazzo

First, we need recent btrfs tools. Otherwise, we're entering a world of pain.

So:

apt-get build-dep btrfs-tools
apt-get install liblzo2-dev libblkid-dev
git clone git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs.git
make -j -C btrfs-progs

jpetazzo

So this is on my "puny" i7, which is a "Intel(R) Core(TM) i7-2720QM CPU @ 2.20GHz".
During the bench I think it was running at 2 GHz, and it's supposed to be able to boost at 3.3 GHz.
(But I hard-capped the speed because I don't like when my laptop starts to levitate because of fanspeed ;-))


The 'numbers' are in 1000s of bytes per second processed.
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
md2                  0.00         0.00         0.00         0.00         0.00 
mdc2                 0.00         0.00         0.00         0.00         0.00 
md4              21071.83k    63368.19k   147767.22k   221280.60k   258719.74k

jpetazzo

#!/bin/sh
# Set minimal MTU to an impossible amount.
MINMTU=99999

INTERFACES=$(ip ro list | grep ^default | sed 's/.*dev \([^ ]*\) .*/\1/')
for I in $INTERFACES
do
  MTU=$(ip link show $I | grep mtu | sed 's/.*mtu \([^ ]*\) .*/\1/')
  [ $MTU -lt $MINMTU ] && MINMTU=$MTU  
done

jpetazzo

def trace(f):
    def wrapped_f(*args, **kwargs):
        print ("Calling {0} with args={1} and kwargs={2}"
               .format(f.__name__, args, kwargs))
        return_value = f(*args, **kwargs)
        print ("Return value={0!r}".format(return_value))
        return return_value
    return wrapped_f

@trace

jpetazzo

FROM ubuntu
RUN apt-get -qy install tmux openssh-server
CMD \
	ssh-keygen -f /root/.ssh/id_rsa -N "" >/dev/null &&\
	cp /root/.ssh/id_rsa.pub /root/.ssh/authorized_keys &&\
	mkdir /var/run/sshd &&\
	/usr/sbin/sshd &&\
	sleep 1 &&\
	ssh-keyscan localhost > /root/.ssh/known_hosts 2>/dev/null &&\
	ssh -t localhost tmux

jpetazzo

Zerohub

This is used to have a bunch of ZeroRPC clients and workers talking to each other.

WARNING: this is not compatible with heartbeats and streaming!

Clients connect to the "in" side of the hub.

Workers connect to the "out" side of the hub.

jpetazzo

Let's start a container:

root@dockerhost:~# docker run -d -i ubuntu bash
0d62d8b0dc65998b0dc5b88d4e2bd331f560579199f05869088ac98266dac0b1

Now let's check the cgroup values:

jpetazzo

package main

import "fmt"

type Base struct {
}

func (b *Base) Area () int {
	return 2*b.Radius()
}

jpetazzo

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet dhcp