Archive for the ‘Linux Audio & Video’ Category

How to get rid of Debian and Ubuntu GNU / Linux obsolete configuration files and system directories

Wednesday, October 19th, 2011

debian_ubuntu-linux-get-rid-of-obsolete-files
I've been using Debian GNU / Linux on my Thinkpad laptop for almost 3 years and half. Initially the Debian version which I had installed was a stable Debian Lenny. As I was mostly dissatisfied of the old versions of the programs, I migrated to testing / unstable
Testing / unstables shipped program versions were a bit better but still back in the day I wanted to get advantage of the latest program versions so for a while I switched to unstable .
Later I regretted for this bad idea, after the migration to Unstable, it was too buggy to run on a notebook one uses for everyday work.
Then to revert back to a bit stable I downgraded to testing unstable again.
When Debian launched Debian Squeeze I set in my /etc/apt/sources.list file software repositories to be the one for the stable Debian Squeeze.

As you can see, I've done quite a lot of "experiments" and "excersises". Many packages were installed, then removed, some became obsolete with time others I just temporary installed out of curiosity. Anyways as a result I ended up with many packages uninstalled / removed , which still kept some of their directory structres and configurations on the machine.

Today, I decided to check how many of these obsolete packages are still present in dpkg database and I was shocked to find out 412 debs were still in my package database! To check the number I used cmd:

root@noah:~# dpkg -l | grep -i '^rcs.*$'|wc -l

Considering the tremendous number of packs waiting to be purged, I decided to get rid of this old and already unnecessery files for the sake of clarity, besides that removing the old already uninstalled packages removes old configuration files, readmes, directories and frees some little space and therefore frees some inodes 😉

Before proceeding to remove them, I carefully reviewed and all the package names which I was about to completely purge in order to make sure there is no package with a configuration files I might need in future:

root@noah:~# dpkg -l |grep -i '^rcs.*$'
...
After reviewing all the deb packages possessing the rc – (remove candidate) flag, I used the following bash one liners to remove the obsolete deb packages:

root@noah:~# for i in $(dpkg -l |grep -i '^rcs.*$'|awk '{ print $2 }'); do echo dpkg --purge $i done...
root@noah:~# for i in $(dpkg -l |grep -i '^rcs.*$'|awk '{ print $2 }'); do dpkg --purge $i done

First line will just print out what will be purged with dpkg , so after I checked it out I used the second one to purge all the RC packs.

Non-free packages to install to make Ubuntu Linux Multimedia ready / Post install packages for new Ubuntu installations

Monday, January 23rd, 2012

non-free-packages-to-install-make-ubuntu-linux-multimedia-ready

1. Add Medibuntu package repository

root@ubuntu:~# wget --output-document=/etc/apt/sources.list.d/medibuntu.list \
http://www.medibuntu.org/sources.list.d/$(lsb_release -cs).list \
&& apt-get --quiet update \
&& apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring \
&& apt-get --quiet update

2. Enable Ubuntu to play Restricted DVD
root@ubuntu:~# apt-get install --yes libdvdread4
...
root@ubuntu:~# /usr/share/doc/libdvdread4/install-css.sh

After that VLC will be ready to play DVDs for some programs which was compiled without DVD, source rebuilt is required.

If DVDs hang you might need to set a Region Code with regionset:

# regionset

3. Install non-free codecs

root@ubuntu:~# apt-get install non-free-codecs

4. Install Chromium ffmpeg nonfree codecs

root@ubuntu:~# apt-get install chromium
root@ubuntu:~# apt-get install chromium-codecs-ffmpeg-nonfree

5. Install w32codecs / w64codecs

Depending on the Ubuntu Linux installation architecture 32/64 bit install w32codecs or w64codecs

For 32 bit (x86) Ubuntu install w32codecs:

root@ubuntu:~# apt-get install w32codecs

For 64 bit arch Ubuntu:

root@ubuntu:~# apt-get install w64codecs

6. Install ubuntu-restricted-extras meta package

root@ubuntu:~# apt-get install ubuntu-restricted-extras

7. Install cheese for webcam picture/video snapshotting

root@ubuntu:~# apt-get install cheese

8. Install GIMP, Inkscape, xsane,sane, shotwell etc.

root@ubuntu:~# apt-get --yes install sane xsane gimp inkscape gimp-data-extras gimp-plugin-registry \
blender gcolor2 showtwell bluefish kompozer

9. Install multimedia Sound & Video utilities

Install Subtitle editor, video editiking , sound editing, mp3 player, iso mounters, DVD/CD Burners

root@ubuntu:~# apt-get install rhythmbox banshee smplayer mplayer \
realplayer audacity brasero jokosher istanbuk gtk-recordMyDesktop \acetoneisohexedit furiusisomount winff fala audacious dvdstyler lives hydrogen
subtitleeditor gnome-subtitles electricsheep k3b

10. Install CD / DVD RIP tools

root@ubuntu:~# apt-get install acidrip sound-juicer ogmrip thoggen
11. Install chat messanger programs, Browsers, mail pop3 clients, torrent, emulators, ftp clients etc.

apt-get install seamonkey thunderbird transmission transmission-gtk gbgoffice kbedic \
pidgin openoffice.org gxine mozilla-plugin-vlc wine dosbox samba filezilla amsn ntp \epiphany-browser ntpdate desktop-webmail alltray chmsee gftp xchat-gnome ghex \gnome-genius bleachbit arista

12. Install Non-Free Flash Player

Unfortunately Gnash is not yet production ready and crashes in many websites …

root@ubuntu:~# apt-get install flashplugin-nonfree flashplugin-nonfree-extrasound swfdec-gnome

13. Install Archive / Unarchive management programs

root@ubuntu:~# apt-get install unace unrar zip unzip p7zip-full p7zip-rar sharutils rar uudeview \
mpack lha arj cabextract file-roller

15. Install VirtualBox and QEmu

root@ubuntu:~# apt-get install qemu-launcher qemu-kvm-extras virtualbox virtualbox-ose \
virtualbox-ose-guest-dkms virtualbox-ose-guest-dkms

This should be enough to use Ubuntu normally for multimedia Desktop just as MS Windows for most of the daily activities.
Am I missing some important program?

How to add (.srt , .sub) subtitles to .flv flash movie video on Linux

Friday, April 15th, 2011

how-to-add-srt-subtitles-to-flv-flash-movie-video-on-linux
If you're on Linux the questions like, how can I convert between video and audio formats, how to do photo editing etc. etc. have always been a taugh question as with it's diversity Linux often allows too many ways to do the same things.

In the spirit of questioning I have been recently curious, how can a subtitles be added to a flash video (.flv) video?

After some research online I've come up with the below suggested solution which uses mplayer to do the flash inclusion of the subtitles file.

mplayer your_flash_movie.flv -fs -subfont-text-scale 3

While including the subtitles to the .flv file, it's best to close up all the active browsers and if running something else on the desktop close it up.
Note that above's mplayer example for (.srt and .sub) subtitle files example is only appropriate for a .flv movie files which already has a third party published subtitle files.

What is interesting is that often if you want to make custom subtitles to let's say a video downloaded from Youtube on Linux the mplayer way pointed above will be useless. Why?

Well the Linux programs that allows a user to add custom subtitles to a movie does not support the flv (flash video) file format.

My idea on how to create custom subtitles and embed them into a flv movie file is very simple and it goes like this:

1. Convert the .flv file format to let's say .avi or .mpeg
2. Use gnome-subitles or subtitleeditor to create the subtitles for the .avi or .mpeg file
3. Convert back the .avi/.mpeg file with included subtitles to .flv (flash video format)

This methodology is really long and time consuming, but pitily as far as my understanding goes it's the only way to do that on your Linux until now.

To make the conversations between .flv and .avi format you will need to use the ffmpeg – (FFMpeg command line tool video converter), here is how:

– Convert .flv to .avi

debian:~# /usr/bin/ffmpeg -i input_flvfilename.flv output_avifilename.avi

– Convert .avi file to .flv

debian:~# /usr/bin/ffmpeg -y -i /path/to/your/avi/input_avifilename.avi -acodec mp3 -ar 22050 -f flv
/path/to/your/flv/output_flvfilename.flv

The required overall tools which you will have to have installed on your Debian or Ubuntu Linux are:

1. ffmpeg
2. gnome-subtitles
3. subtitleeditor
4. mplayer

You will also have to spend some time to get to know gnome-subtitles or subtitleeditor, but it won't be that long until you get the idea on how to use them.

Updating Flash Player on Debian GNU / Linux / Keeping Flash player up-to-date with update-flashplugin-nonfree

Saturday, November 10th, 2012

 

Update flash player on Debian GNU / Linux update-flashplugin-nonfree macromedia flash logo

Assuming you have previously installed and running Adobe Flash Player – package flashplugin-nonfree i.e.:

debian:~# dpkg -l |grep -i flashplugin-nonfree
ii flashplugin-nonfree 1:2.8.3 Adobe Flash Player - browser plugin

and you want to Update flash player to the latest provided version for Linux, there is an update script part of flashplugin-nonfree, package /usr/sbin/update-flashplugin-nonfree. The script updates flash player to latest Linux version avaiable fetching the version from macromedia's website in a .tar.gz and untarring it substituting the old flash library.

To update your Debian FlashPlayer, launch as superuser:

debian:~# update-flashplugin-nonfree --install
--2012-11-10 00:51:48-- http://fpdownload.macromedia.com/get/flashplayer/pdc/11.2.202.251/install_flash_player_11_linux_x86_64.tar.gz Resolving fpdownload.macromedia.com... 92.123.98.70 Connecting to fpdownload.macromedia.com|92.123.98.70|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 7228964 (6.9M) [application/x-gzip] Saving to: “./install_flash_player_11_linux_x86_64.tar.gz”

0K .......... .......... .......... ..........
.......... 0% 69.5K 1m41s 50K .......... .......... .......... ..........
.......... 1% 91.1K 88s 100K .......... .......... .......... ..........
.......... 2% 70.8K 91s ........
..........

After a while (usually up to a minute), update will be completed. Restart your browser of use IceWeasel, Epiphany, Opera, Chrome etc. and test it with About Flash Player Page and / or youtube. You should be with latest Flash Linux version now.

It might be a good idea to automate future flash player updates via a cron job, I think launching the update script every two weeks is a good timing;

To do so add to root user cron like so:

10,27 * * * * /usr/sbin/update-flashplugin-nonfree –install -q 2>&1 >/dev/null

If you still haven't configured your pulseaudio to play multiple sound streams do that too.

I've seen also on Debian's Wiki FlashPlayer page, mentioning that on some systems after update to Flash Player 11 there might be laggy performance issues, due to disabled hardware acceleration in Flash Player > v. 10. If that's the case with you you might also need to put a mss.cfg like this one to /etc/adobe/mss.cfg

# wget -q https://www.pc-freak.net/files/adobe-flash-player-config-for-hardware-acceleration-mms.cfg
# mv adobe-flash-player-config-for-hardware-acceleration-mms.cfg /etc/adobe/mms.cfg

Finally if you experience, some flash video lagging issues, you could try experimenting with OverrideGPUValidation=true flash setting which in some cases improves Linux flash video performance

Firefox users might be also interested to check out www.mozilla.org/en-US/plugincheck – the URL provides information on essential Firefox video plugins and whether plugins installed are up2date or prone to remote web exploitation vulnerability.

Free Software Songs and Videos Collection – (Anthem of Free Software) various interpretations

Friday, November 18th, 2011

Richard Stallman picture

I've gathered a collection of 15 Audio and Video songs dedicated to the Free Software / Open Source movement . All of the songs are based on the The Free Software Song Anthem written by Richard Mathew Stallman in the year 1991. The motive of the song is a Traditional Bulgarian song called Sadi Moma Bqla Loza – translated to bulgarian to something like Maid is Planting white Vines
The original Free Software Song symbolizes all free software and the Free Software Movement and GNU and is in the Bulgarian unique / specific folk rhythm of 7 / 8 beats .

Most of the songs which I post hereby could also be found and downloaded from GNU's official Free Software Song page
However some of the songs were only available from Youtube in the non-free format Flash Video (flv) . Hence, since the songs were dedicated to Free Software and apparently were being spread in a non-free format they either was missing any licensing or licensed under GFDL free music / art GNU like license.
To fix up this irragularity and add some freedom in terms of audio format of spreading, I've downloaded them and used ffmpeg2theora to convert the songs to the Free / Open Standard format Ogg Vorbis
I'm quite sure that many people, who use Ubuntu or Linux Mint are pretty much unfamiliar with the Free Software Songs existence, also many people most likely have never heard the Free Software Songs or even those who heard it have rarely heard more than 2 or 3 of the song variations.
Hereby, I'm sure many people who are lovers of Free Software will highly benefit and get inspired to continue in the Free Software by listening to these post shared little Free Software Song Collection .

The covers of the Original version publicly sang by Richard Stallman are in different musical genres, some of the song performances are in Folklore, played on Piano other covers are performed by musical bands in pop / punk en popular music styles, there are one person performances, cheerful christmas like soundings, 8 bit free software song, Metal free software variations etc. In the collection I've included also few other nice songs which are propaganda on free software, even though not a cover of the Free Software Song , I found them myself worthy to be included in the collection..:

Herein you can download or listen all the Free Software Songs version (Enjoyment is guaranteed! 😉 ):















Fenster-Free-Software-Song.ogg
Free_Software_Song_en_español.ogv
Free_Software_Song_feat._Flat_Eric.ogv
Jono_Bacon_-_-Free_Software_Song_2_Metal_Version.ogv
Markushaist_piano_-free-software-song.ogg
Metal_Free_Software_Song_v2.0.ogv
Stallman_Free_Software_Song_Video_320x240.ogv
The_Gnu_Song.ogv
The_Pink_Stainless_Tail_Free_Software_Song.ogv
free-software-song-herzog.ogg
free-software-song-rhythmic.ogg
free_software_song_sunnata.ogg
freesoft.ogg
jonobacon-freesoftwaresong2.ogg
pjj-and-hairyone-freesoftwaresong.ogg
I've also prepared a bundle containing all the 15 Free Software Songs which you can download from here
Enjoy the nice music! Don't forget to share it with everyone you could among with educating the people how important it is to value their freedom in this age of technological human enslavement 😉
 

How much memory users uses in GNU / Linux and FreeBSD – Commands and Scripts to find user memory usage on Linux

Tuesday, February 17th, 2015

 

how-much-memory-users-use-in-gnu-linux-freebsd-command-to-find-and-show-ascending-descending-usage-of-system-memory-tux-memory-logo

 


If you have to administrate a heterogenous network with Linux and FreeBSD or other UNIX like OSes you should sooner or later need for scripting purposes to have a way to list how much memory separate users take up on your system. Listing memory usage per user is very helpful for admins who manager free-shells or for companies where you have developers, developing software directly on the server via ssh. Being able to check which process eats up most memory is essential for every UNIX / Linux sysadmin, because often we as admins setup (daemons) on servers and we forgot about their existence, just to remember they exist 2 years later and see the server is crashing because of memory exhaustion. Tracking server bottlenecks where RAM memory and Swapping is the bottleneck is among the main swiss amry knives of admins. Checking which user occupies all server memory is among the routine tasks we're forced to do as admins, but because nowdays servers have a lot of memory and we put on servers often much more memory than ever will be used many admins forget to routinely track users / daemons memory consumption or even many probably doesn't know how.  Probably all are aware of the easiest wy to get list of all users memory in console non interactively with free command, e.g.:
 

free -m
             total       used       free     shared    buffers     cached
Mem:         32236      26226       6010          0        983       8430
-/+ buffers/cache:      16812      15424
Swap:        62959        234      62725

 

but unfortunately free command only shows overall situation with memory and doesn't divide memory usage by user

Thus probably to track memory users the only known way for most pepole is to (interactively) use good old top command or if you like modern (colorful) visualization with htop:

debian:~# top

 

linux-check_memory_usage_by_logged-in-user-with-top-process-command-gnu-linux-freebsd-screenshot

Once top runs interactive press 'm' to get ordered list of processes which occupy most system memory on Linux server.Top process use status statistics will refresh by default every '3.0' seconds to change that behavior to '1' second press  s and type '1.0'. To get Sort by Memory Use in htop also press 'm'
 

[root@mail-server ~]# htop


htop_show_users_memory_usage_order_ascending-gnu-linux-screenshot

 

However if you need to be involved in scripting and setting as a cron job tasks to be performed in case if high memroy consumption by a service you will need to use few lines of code. Below are few examples on how Linux user memory usage can be shown with ps cmd.

Probably the most universal way to see memory usage by users on Debian / Ubuntu / CentOS / RHEL and BSDs (FreeBSD / NetBSD) is with below one liner:

 

server:~# ps hax -o rss,user | awk '{a[$2]+=$1;}END{for(i in a)print i” “int(a[i]/1024+0.5);}' | sort -rnk2
daemon 0
debian-tor 63
dnscache 1
dnslog 0
hipo 21
messagebus 1
mysql 268
ntp 2
privoxy 1
proftpd 1
qmaill 0
qmailq 0
qmailr 0
qmails 0
qscand 291
root 94
shellinabox 1
snmp 1
statd 1
vpopmail 80
www-data 6765

 

Output is in MBs

Below is output from machine where this blog is running, the system runs ( Apache + PHP + MySQL Webserver + Qmail Mail server and Tor) on Debian GNU / Linux.

 To get more human readable (but obscure to type – useful for scripting) output list of which user takes how much memory use on deb / rpm etc. based Linux :

 

server:~# echo "USER                 RSS      PROCS" ; echo "——————– ——– —–" ; \
ps hax -o rss,user | awk '{rss[$2]+=$1;procs[$2]+=1;}END{for(user in rss) printf “%-20s %8.0f %5.0f\n”, user, rss[user]/1024, procs[user];}' | sort -rnk2

 

USER                 RSS      PROCS
——————– ——– —–
www-data                 6918   100
qscand                    291     2
mysql                     273     1
root                       95   120
vpopmail                   81     4
debian-tor                 63     1
hipo                       21    15
ntp                         2     1
statd                       1     1
snmp                        1     1
shellinabox                 1     2
proftpd                     1     1
privoxy                     1     1
messagebus                  1     1
dnscache                    1     1
qmails                      0     2
qmailr                      0     1
qmailq                      0     2
qmaill                      0     4
dnslog                      0     1
daemon                      0     2

 

It is possible to get the list of memory usage listed in percentage proportion, with a tiny for bash loop and some awk + process list command
 

TOTAL=$(free | awk '/Mem:/ { print $2 }')
for USER in $(ps haux | awk '{print $1}' | sort -u)
do
    ps hux -U $USER | awk -v user=$USER -v total=$TOTAL '{ sum += $6 } END { printf "%s %.2f\n", user, sum / total * 100; }'
done

107 1.34
115 2.10
119 1.34
daemon 1.32
dnscache 1.34
dnslog 1.32
hipo 1.59
mysql 4.79
ntp 1.34
privoxy 1.33
proftpd 1.32
qmaill 1.33
qmailq 1.33
qmailr 1.32
qmails 1.33
qscand 4.98
root 1.33
snmp 1.33
statd 1.33
vpopmail 2.35
www-data 86.48

Also a raw script which can be easily extended to give you some custom information on memory use by user list_memory_use_by_user.sh is here.
You can also want to debug further how much memory a certain users (lets say user mysql and my username hipo) is allocating, this can easily be achieved ps like so:
 

root@pcfreak:~# ps -o size,pid,user,command -u mysql –sort -size
 SIZE   PID USER     COMMAND
796924 14857 mysql   /usr/sbin/mysqld –basedir=/usr –datadir=/var/lib/mysql –plugin-dir=/usr/lib/mysql/plugin –user=mysql –pid-file=/var/run/mysqld/mysqld.pid –socket=/var/run/mysqld/mysqld.sock –port=3306

 

root@pcfreak~# ps -o size,pid,user,command -u hipo –sort -size|less
 SIZE   PID USER     COMMAND
13408 19063 hipo     irssi
 3168 19020 hipo     SCREEN
 2940  2490 hipo     -bash
 1844 19021 hipo     /bin/bash
 1844 19028 hipo     /bin/bash
 1844 19035 hipo     /bin/bash
 1844 19042 hipo     /bin/bash
 1844 19491 hipo     /bin/bash
 1844 22952 hipo     /bin/bash
  744  2487 hipo     sshd: hipo@pts/0
  744  2516 hipo     sshd: hipo@notty
  524  2519 hipo     screen -r
  412  2518 hipo     /usr/lib/openssh/sftp-server

You see from below output user running with www-data (this is Apache Webserver user in Debian) is eating 86.48% of overall system memory and MySQL server user is using only 4.79% of available memory

Output is shown in Megabytes per username memory usage, and user memory usage is ordered (stepping-down / descentive) from top to bottom

Getting more thoroughful and easier to read reporting without beeing a 31337 bash coder you can install and use on Linux smem – memory reporting tool .

SMEM can provide you with following memory info:

  • system overview listing
  • listings by process, mapping, user
  • filtering by process, mapping, or user
  • configurable columns from multiple data sources
  • configurable output units and percentages
  • configurable headers and totals
  • reading live data from /proc
  • reading data snapshots from directory mirrors or compressed tarballs
  • lightweight capture tool for embedded systems
  • built-in chart generation


Installing smem on Debian 6 / 7 / Ubuntu 14.04 / Turnkey Linux etc. servers is done with standard:

 

debian:~# apt-get install –yes smem
….

 

 

To install smem on CentOS 6 / 7:

 

[root@centos ~ ]# yum -y install smem
….


On Slackware and other Linux-es where smem is not available as a package you can install it easily from binary archive with:

 

cd /tmp/
wget http://www.selenic.com/smem/download/smem-1.3.tar.gz
tar xvf smem-1.3.tar.gz
sudo cp /tmp/smem-1.3/smem /usr/local/bin/
sudo chmod +x /usr/local/bin/smem

 


Two most common smem uses are:

 

root@mail:~# smem -u
User     Count     Swap      USS      PSS      RSS
dnslog       1       44       48       54      148
qmaill       4      232      124      145      464
hipo        11    13552     8596     9171    13160
qscand       2     4500   295336   295602   297508
root       188   217312  4521080  4568699  7712776

 

Below command shows (-u – Report memory usage by user, -t – show totals, -k – show unix suffixes)

root@mail:~# smem -u -t -k
User     Count     Swap      USS      PSS      RSS
dnslog       1    44.0K    48.0K    54.0K   148.0K
qmaill       4   232.0K   124.0K   145.0K   464.0K
hipo        11    13.2M     8.4M     9.0M    12.9M
qscand       2     4.4M   288.4M   288.7M   290.5M
root       188   212.2M     4.3G     4.4G     7.4G
—————————————————
           206   230.1M     4.6G     4.6G     7.7G


To get users memory use by percentage with smem:
 

root@mail:~# smem -u -p
User     Count     Swap      USS      PSS      RSS
dnslog       1    0.00%    0.00%    0.00%    0.00%
qmaill       4    0.00%    0.00%    0.00%    0.01%
hipo        11    0.17%    0.11%    0.11%    0.16%
qscand       2    0.05%    3.63%    3.63%    3.66%
root       194    2.64%   56.18%   56.77%   95.56%

It is also useful sometimes when you want to debug system overloads caused by external hardware drivers loaded into kernel causing issues to get list of system wide memory use sorted by user

 

 root@mail:~# smem -w -p
Area                           Used      Cache   Noncache
firmware/hardware             0.00%      0.00%      0.00%
kernel image                  0.00%      0.00%      0.00%
kernel dynamic memory        38.30%     36.01%      2.28%
userspace memory             60.50%      0.98%     59.53%
free memory                   1.20%      1.20%      0.00%


smem is very nice as if you're running it on a Desktop Linux system with Xserver installed you can see also graphical output of memory use by application:
 

root@desktop-pc:~# smem –bar pid -c "pss uss"


smem_graphical_representation-of-which-user-application-is-consuming-most-memory-gnu-linux-kde-screenshot-smem-command-line-tool

smem can even generate graphical pie charts to visualize better memory use
 

root@desktop-pc:~# smem -P '^k' –pie=name

 

generate-graphical-staticstics-linux-memory-use-by-pie-chart

If there is a high percentage shown in firmware/hardware this means some buggy module is loaded in kernel eating up memory, to fix it debug further and remove the problematic module.
userspace memory actually shows the percantage of memory out of all server available RAM that is being consumed by applications (non kernel and other system processes which make the system move). You see in above example the kernel itself is consuming about 40% of system overall available memory. 

We all know the SWAP field stands for hard disk drive used as a memory when system is out, but there are 3 fields which smem will report which will be probably unclear for most here is also explanation on what USS / PSS / RSS means?

RSS is the Resident Set Size and is used to show how much memory is allocated to that process and is in RAM. It does not include memory that is swapped out. It does include memory from shared libraries as long as the pages from those libraries are actually in memory. It does include all stack and heap memory too.

There is also PSS (proportional set size). This is a newer measure which tracks the shared memory as a proportion used by the current process. So if there were two processes using the same shared library from before.

USS stands for Unique set size, USS is just the unshared page count, i.e. memory returned when process is killed 

PSS = Proportional set size, (PSS),  is a more meaningful representation of the amount of memory used by libraries and applications in a virtual memory system.  
Because large portions of physical memory are typically shared among multiple applications, the standard measure of memory usage known as resident set size (RSS) will significantly overestimate memory usage. The parameter PSS instead measures each application’s “fair share” of each shared area to give a realistic measure. For most admins checking out the output from RSS (output) should be enough, it will indicate which user and therefore which daemon is eating up all your memory and will help you to catch problematic services which are cause your server to run out of RAM and start swapping to disk.

Create video from linux console / terminal – Record ssh terminal session as video with asciinema, showterm, termrecord

Thursday, August 21st, 2014

/var/www/images/asciinema-create-and-upload-ascii-terminal-console-videos-debian-gnu-linux-screenshot
You probably already know of existence of two Linux commands available by default across all Linux distributions scriptwhich makes a text based save of all commands executed on console and scriptreplay – which playbacks saved script command typescripts. Using this two you can save terminal sessions without problem, but in order to play them you need to have a Linux / UNIX computer at hand.
However If you want to make a short video record displaying what you have done on Linux console / terminal, you have few other options with which you can share your Linux terminal sessions on the web. In this short article I will go through 3 popular tools to do that – asciinema, showterm and termrecord.

1. Asciinema Current most popular tool to create video from Linux terminal

Here is how ASCIINEMA's website describes it:

"Asciinema is a free and open source solution for recording the terminal sessions and sharing them on the web."

apt-get –yes install python-pip

To install it with pip python package installer

pip install asciinema

Or if the machine is in DMZ secured zone and have access to the internet over a Proxy:

pip install –proxy=http://internet-proxy-host.com:8080 asciinema

It will get installed in /usr/local/bin/asciinema to make a terminal screen video capture just launch it (nomatter if it is privileged or non-privileged user):

asciinema

To finalize and upload the recorded terminal session, just type exit (to exit the shell), hopefully it will get you an upload link.

exit

You can claim authorship on video you issue:

asciinema auth

Use can then embed the new Linux terminal session video to your website.
 

2. ShowTerm – "It's showtime in a terminal near you!"

ShowTerm have same features as AsciiNema. Just like AsciiNema, what it does is it creates a record of your terminal session and then uploads it to showterm.io website, providing you a link over which you can share your terminal lesson / ascii art video / whatever with your friends. ShowTerm is written in, the world famous Ruby on Railsruby web development framework, so you will need to have ruby programming language installed before use. As showterm uses the Internet to upload video, so it is not really an option to create videos from remote terminal session on servers which are in DMZ with no access to the internet, I will explain in a little while how to create video of your terminal / console for private purpose on local server and then share it online on your own site.

a) To install ShowTerm:

– First be sure to have ruby installed:

On Debian / Ubuntu and derives deb Linux, as supersuser:

apt-get install –yes ruby curl

On CentOS / RHEL / Fedora Linux

yum -y install ruby curl

NB! curl is real requirement but as showterm.io website recommends downloading the script with it and later same curl tool is used to upload the created showterm file to http://showterm.io .

– Then to finalize install, download showterm script and make it executable

curl showterm.io/showterm > ~/bin/showterm

% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                       Dload  Upload   Total   Spent    Left  Speed
100  2007  100  2007    0     0   2908      0 –:–:– –:–:– –:–:–  8468

mkdir ~/bin
chmod +x ~/bin/showterm

This will save the script into your home folder ~/bin/showterm

b) Using showterm

To run it to create video from your terminal simply start it and do whatver you will in terminal.

~/bin/showterm

After you're done with the video you like type exit

exit

create-video-from-your-linux-console-terminal-with-showterm-screenshot

Note that if your server is behind a proxy curl will not understand proxy set inside Linux shell variable with http_proxy var, to upload the file if you're behind a proxy you will have to pass to curl –proxy setting, once you get the curl line invoked after failure to upload use something like:

curl –proxy $(echo $http_proxy)  https://showterm.herokuapp.com/scripts –data-urlencode cols=80 –data-urlencode lines=24 –data-urlencode scriptfile@/tmp/yCudk.script –data-urlencode timingfile@/tmp/lkiXP.timing

Where assuming proxy is defined already inside http_proxy shell variable.

 

3. Creating video from your terminal / console on Linux for local (private) use with TermRecord

In my humble view TermRecord is the most awesome of all the 3, as it allows you to make records with an own generated Javascript based video player and allows you to keep the videos on your own side, guaranteeing you independence of external services. Its
 

pip install TermRecord

TermRecord -o /tmp/session.html

 

You can further access the video in a local browser in Firefox / Chrome / Epiphany type in URL address bar:

/tmp/session.html to play the video

create-video-from-terminal-console-on-gnu-linux-howto-screenshot-with-termrecord

TermRecord uses term.js javascript to create the video web player and play the video which is directly encoded inside session.html.
If you want to share the video online, place it on your webserver and you're done 🙂
Check out my TermRecord generated video terminal sample session here.
 

Quick shortcut to lock your Linux computer desktop (Few words on Linux screensavers)

Thursday, November 20th, 2014

quick-way-to-lock-desktop-linux-howto-key
Locking the PC while going for a coffee break, Lunch or toilet is longly used to secure physically your PC display from spying eyes or prevent you from  someone to install a spying software or leak private data from PC HDD to an USB drive.
People who are coming from the wonderful MS Windows OS   are certainly used to quick shortcut key combination to lock PC screen with:
 

Windows key + L

 

So how to do Lock Screen on Linux?

On Linux locking your Screen the Quick Shortcut is:
 

CTRL + ALT + L.


Locking the screen is done (depending on the Linux distribution) by using by either using historically famous XScreenSaver if non-gnome / KDE graphical environemnt is used or if in Linux Gnome GUI with  gnome-screensaver and on KDE desktop manager with kscreenlocker.

 

Exact command executed on CTRL + ALT + L keypress on GNOME is:
 

gnome-screensaver-command -l


On KDE to manually lock screen command is:

kscreenlocker

Nomatter whether with GNOME or KDE its worthy mention that xscreensaver is more Screensaver rich than kscreenlocker and gnome-screensaver as it includes about 200 different Screensavers making screen nice to watch when you come back from a lunch.

For people with Windows key keyboard who are too used to using Windows XP / 7 lockreen WIN + L key shortcut to make Windows (key) + L keys combination work on Linux with GNOME desktop:
 

System -> Preferences -> Keyboard Shortcuts

Make Win + L keys combination work on Linux with KDE desktop
 

  1.  "System Settings" (KDE menu).
  2. Choose "Keyboard & mouse" (on "General" tab).
  3. Choose "Global Keyboard Shortcuts" on the left.
  4. Choose "Run Command Interface" from "KDE component" dropdown list.
  5. Choose "Lock session".
  6. Select "Custom".
  7. Click on "None" (button changes to "Input…").
  8. Compose your desired sequence by pressing appropriate buttons on your keyboard.
  9. Click "Apply".

 


For other desktop environments like Window Maker you can use xmodmap command to bind Win + L keys

festival “Linux: can’t open /dev/dsp” error fix

Wednesday, September 16th, 2009

I tried using festival today just to realize it doesn’t work anymore.
For instance # echo test |festival -tts would fail with the annoying
“Linux: can’t open /dev/dsp”  error message. I found the solution in ubuntuforums,
the solution is originally taken from “the Gentoo Speechd Howto“.
The solution is to create .festivalrc in your home as well as to the homes of all usersintending to use festival.
Here is how:

printf ";use ALSAn(Parameter.set 'Audio_Method 'Audio_Command)n(Parameter.set 'Audio_Command "aplay -q -c 1 -t raw -f s16 -r $SR $FILE")n" > .festivalrc

Downloading your favourity flash video from Youtube with a simple command (youtube-dl)

Wednesday, April 13th, 2011

downloading-flash-videos-from-youtube-on-linux-and-bsd-youtube-downloader-logo
Watching videos in youtube today and already for about 2 years is the de-facto hype.
There is almost none a day passed without almost each one of us has watched a dozen videos in Youtube.

Watching videos in youtube has become even more addictive for many than the early days of Internet Relay Chats (IRC)

As youtube is very accessible for people and it’s a comparativily easy way people share more and more with the day.
There is no question that the business idea of youtube is great and youtube generates millions of dollars for Google day by day, however I have a serious objection here! All is good the only pitfall is that you don’t own the youtube videos you watch!

Youtube’s story is not that different from the story of the cloud computing threat to internet users Freedom

The good thing here is that we’re not still completely dependant on youtube and there is still way to retrieve your favourite youtube video and store it for later watching or distribution.

Probably the most famous browser plugin that allows files retrieval from youtube, as most people know is DownloadHelper .

However using download helper is browser dependant, you need to use the browser to save the plugin and I don’t find it to be the best way to download a youtube video.

Since the old days I have started using Linux, I’ve been quite addicted to as many things on my linux as possible from the command line (terminal / console) (CLI) .

In that manner of thoughts it was a real delight for me to find out that a group of free software developer guys has come up with a command line tool that allows downloads of youtube videos straight from terminal, the great software is called youtube-dl and at the moment of this post writting it’s to be found on the URL address:

http://rg3.github.com/youtube-dl/

Youtube-dl is written in python so, it requires the Python interpreter, version 2.5 in order to properly run on Unix, Mac OS X or even on Windows!

The fact that it’s written in python has made the little shiny tool quite a multi-platform one.
To start using immediately the tool on a Debian or Ubuntu Linux you will have to install python (even though in most cases you must have it already installed):

1. To make sure you have python interpreter installed issue the cmd:

debian:~# apt-get install python
Building dependency tree
Reading state information... Done
python is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

As you can see from above apt-get’s output I do have it installed so nothing gets installed.

2. As a next step I used links to download the youtube-dl python script, like so:

debian:~# links https://github.com/rg3/youtube-dl/raw/2011.03.29/youtube-dl >> youtube-dl
Use the links interface to save youtube-dl and use gzip to ungzip it
debian:~# gzip -d youtube-dl.gz
debian:~# chmod +x youtube-dl

Now to make it system wide accessible I have copied the youtube-dl to /usr/local/bin , whether I selected /usr/local/bin as a location as this location is predetermined to contain mostly files which does not belong to a regular deb package.

3. Move youtube-dl to /usr/local/bin

debian:~# mv youtube-dl /usr/local/bin

4. Test the newly installed youtube-dl command line youtube retrieval tool:

debian:~# ./youtube-dl https://www.youtube.com/watch?v=g7tvI6JCXD0
[youtube] Setting language
[youtube] g7tvI6JCXD0: Downloading video webpage
[youtube] g7tvI6JCXD0: Downloading video info webpage
[youtube] g7tvI6JCXD0: Extracting video information
[download] Destination: g7tvI6JCXD0.flv
[download] 53.3% of 22.62M at 33.23k/s ETA 05:25
[download] 100.0% of 22.62M at 31.91k/s ETA 00:00 [u

As you might have noticed from the above youtube-dl command output the newly retrieved youtube file will be saved under a name g7tvI6JCXD0.flv

The line I passed to youtube-dl is directly taken from my browser and pasted to console, the file downloading from youtube took me about 10 minutes but this is mostly because of some kind of youtube server speed restrictions …

In general at least I have this video for later, watching, so after a while I can watch it once again without loosing a lot of time trying to remember what was the video headline name

5. To use youtube-dl in a bit advanced way you can for instance invoke the command with options like:

debian:~# ./youtube-dl -l -w -c https://www.youtube.com/watch?v=g7tvI6JCXD0
[youtube] Setting language
[youtube] g7tvI6JCXD0: Downloading video webpage
[youtube] g7tvI6JCXD0: Downloading video info webpage
[youtube] g7tvI6JCXD0: Extracting video information
[download] Destination: BSD is Dying, Jason Dixon, NYCBSDCon 2007-g7tvI6JCXD0.flv
[download] 4.4% of 22.62M at 1.43M/s ETA 00:15

As you can see now youtube-dl was even able to detect the downloaded video file name and store it on the computer with a correct name 😉

I would recommend you also to check out the youtube-dl help page, to do use command: youtube-dl –help