I enjoy maté as a substitute for coffee. The best way for me to prepare Maté is not by using the traditional bombilla and gourd, but instead I prefer to use a Moka Pot.
This produces a rather concentrated Maté brew which can be mixed with milk or drunk as is.
Something I have been thinking about is to pulverize the coarse Maté in a coffee grinder before brewing as a way to extract more. I’ll update this post with the results.
Not nix related, but this is a blog.
The best media box software out there has been released in a new version – XBMC 11 Eden.
Initially I was very pleased with this update until I noticed the amount of CPU used while XBMC was idling. 100+% of CPU usage of one core.
After fiddling around with settings like Dirty Regions and not having success – I opted for a more systematic approach.
I went to system settings and immediately noticed a drop in CPU load. I switched between a couple of skins, but the high load began as soon as I entered the main menu.
What differentiated the main menu from the system menu? The RSS news feed in the bottom of the screen!
See here for reference: XBMC Apperance Settings
Turning this off immediately dropped the load to 3-4% when XBMC was idling in the main menu, but reappeared when any kind of GPU work was to be done.
I later found out that this was due to XVBA not being enabled on the XBMC build I was using (I have an ATI card). So, after installing a XVBA enabled build: xvba-xbmc my problem was completely solved.
XVBA is said to be dead (no further development), but it is probably the best solution for ATI owners who use XBMC at the moment.
I became tired using excel to create performance reports and decided to invest some time in creating a template in LaTeX using the fabulous pgfplots package. Since I couldn’t find a suitable example anywhere on the net I’ve decided to share mine here.
Each month I receive bundle of performance statistics from 15 vmware servers which I convert to data looking like this:
2011-12-02 02:00:00, 14.43
2011-12-02 04:00:00, 4.49
2011-12-02 06:00:00, 12.33
2011-12-02 08:00:00, 4.23
2011-12-02 10:00:00, 2.49
2011-12-02 12:00:00, 2.26
2011-12-02 14:00:00, 2.32
2011-12-02 16:00:00, 0.99
2011-12-02 18:00:00, 8.85
2011-12-02 20:00:00, 14.81
...
The extract above is cpu usage of the server every second hour for a month.
\documentclass{minimal}
\usepackage[danish]{babel}
\usepackage[utf8]{inputenc}
\usepackage{palatino}
\usepackage{filecontents}
\usepackage{tikz,pgfplots}
\usepgfplotslibrary{dateplot}
\definecolor{NNITRed}{RGB}{140,0,0}
\definecolor{pengreen}{RGB}{180,204,168}
\begin{document}
\pgfplotstableread[col sep=comma]{/home/regj/code/pyx/data/csv/server.cpud3}
\cputable
\begin{center}
\begin{tikzpicture}
\begin{axis}
[
title=CPU usage,
axis background/.style={fill,bottom color=gray!50,top color=white},
grid=major,
grid style={dotted,black},
width=15cm,
height=8cm,
date coordinates in=x,
date ZERO=2011-12-02 02:00:00,
xmin =2011-12-02 02:00:00,
xmax =2011-12-31 20:00:00,
xtick=,
ymax=100,
ylabel=CPU used \%,
xticklabel style={rotate=90, anchor=near xticklabel}
]
\addplot[blue] table[ y index = 1] from \cputable ;
\addlegendentry{CPU}
\end{axis}
\end{tikzpicture}
\end{center}
\end{document}
Which produces a graph (a very nice one at that IMO):
So, I only want rtorrent to start when a torrent is available for download. I came up with the following script:
while inotifywait -qq -e create /path/to/torrentdir; do
if pgrep rtorrent > /dev/null; then
continue
elif echo /path/to/torrentdir/* | grep torrent; then
screen -d -m -S rtorrent rtorrent
done
I recently discovered the usefulness of fail2ban whilst researching a way to block proxyheader.php requests on my LAMP server.
The request always came from the same location and the same IP’s:
58.218.199.147
58.218.199.250
58.218.199.227
A whois on these IP’s reveal that they’re based in China – Bejing to be exact – and are probably searching for proxy servers to implement in to the Great FW of China
I’m not sure, but their requests annoyed me and I wanted to block them.
I found this filter: Apache Proxy filter , but I found the jail.conf entry did not work and needed to be updated.
Here’s the filter and working jail.conf entry for fail2ban v0.8.4 …
Filter:
# Fail2Ban configuration file
#
# Author: James Roe
# Use in apache access logs
[Definition]
# Matches lines such as:
# 192.168.1.1 - - "GET http://www.infodownload.info/proxyheader.php ...
failregex = ^(?:(?![0-9\.]* -.*"[A-Z]* (/|.*HTTP/1\.[0-9]" (301|302)))
ignoreregex =
Place the filter in /etc/fail2ban/filter.d/apache-proxy.conf.
/etc/fail2ban/jail.local entry:
[apache-proxy]
enabled = true
filter = apache-proxy
action = iptables-multiport[name=PROXY,port="http,https",protocol=tcp]
logpath = /var/log/httpd/*access_log
maxretry = 0
findtime = 604800
bantime = -1
The default image that comes with an Arch Linux linode install is at the time of writing not fully compatible with LVM2. Slash var, usr, and tmp failed when mounted as LVM2 at boot and some very weird errors when creating new LV’s.
I had to do the following to get it to work properly.
# (0) Arch Linux
title Arch Linux [/boot/vmlinuz-linux]
root (hd0)
kernel /boot/vmlinuz-linux-xen root=/dev/xvda ro
initrd /boot/initramfs-linux-xen.img
c0:12345:respawn:/sbin/agetty 38400 tty0 linuxc0:12345:respawn:/sbin/agetty 38400 hvc0 linuxmkdir /mnt/root
mkdir -p /new/{var,srv,home,tmp,usr}
mount /dev/xvda /mnt
mount your lv's to /new/
cp -a /mnt/root/var/* /new/var/ (do this for each new mount point)
rm -rf /mnt/var/* (remove data from each of the directories you transferred to your new lv's)
# /etc/fstab: static file system information.
#
#
proc /proc proc defaults 0 0
/dev/xvda / ext3 noatime,errors=remount-ro 0 1
/dev/xvdb none swap sw 0 0
/dev/mapper/vglino-lvvar /var ext3 noatime 0 1
/dev/mapper/vglino-lvtmp /tmp ext3 noatime 0 1
/dev/mapper/vglino-lvhome /home ext3 noatime 0 1
/dev/mapper/vglino-lvsrv /srv ext3 noatime 0 1
/dev/mapper/vglino-lvbck /data/backup ext3 noatime 0 1
/dev/mapper/vglino-lvusr /usr ext3 noatime 0 1
How would you go about unmounting a mount point from a script that runs on said mount point?
It is clearly not possible with a plain
umount /mnt
since this will immediately unmount the mount point, which will fail with the output
Device busy ...
In case you need to cut the branch the script is sitting on use
umount -l
which entails:
-l Lazy unmount. Detach the filesystem from the filesystem hierarchy now, and cleanup all references to the filesystem as soon as it is
not busy anymore. (Requires kernel 2.4.11 or later.)
So, I decided to upgrade my Windows 7 installation to SP1 using Windows update.
It did not work and returned the error 0x800f0a12, which means that the updater can not access the system partition (the 100MB partition that Win 7 creates during installation).
After some trial and a lot of error I thought it might be caused by my dual boot setup.
I have grub installed on a separate hard drive from where I boot Windows 7 – I use this setup the preserve the Windows 7 boot block – my hunch is that grub ignores the system partition altogether and that’s why Windows 7 can not see it.The solution was:
Wait an hour.
Done.
A post on the Arch forums got me obsessing about running awk without piping anything in to the command i.e. running even external commands from within awk.
The post asked for a way to list installed packages by size and here is what I cooked up:
awk 'BEGIN{while (("pacman -Qi" |getline) > 0){ if ($0 ~ /Name/) {name=$3};\
{if ($0 ~ /Size/) {size=$4/1024;printf "%-25s %d Mb\n", name, size|"sort -k2 -n"}}}}'
It lists packages by size in rounded MB’s sorted by size.
Example output:
gnome-games 51 Mb virtualbox 51 Mb gimp 60 Mb perl 61 Mb texlive-bin 61 Mb llvm 62 Mb gcc 63 Mb python 64 Mb chromium 65 Mb smbclient 66 Mb mysql 67 Mb python2 68 Mb kdelibs 69 Mb evolution 70 Mb samba 73 Mb xulrunner 80 Mb jre 94 Mb qt 109 Mb bin32-jre 110 Mb kernel26 112 Mb kdebase-workspace 113 Mb wine 198 Mb tesseract 212 Mb texlive-core 258 Mb openoffice-base 356 Mb texlive-fontsextra 368 Mb ghc 649 Mb