decide size targets

[ltalirz]

One feedback from Mohamad: In another course, they were asked to download a VM

• zipped VM: 6.6GB
• unzipped VM: 17GB i.e. 25GB of space altogether. This persuaded him to rather install everything by himself.

We are currently at:

• .ova image: 3.0GB
• virtual box size: 7.0GB What should we be aiming for in the "base version"?

Personally, I find 10GB acceptable, but we should be careful to not go too much beyond that. Also, I have never had to space-optimise linux systems, so perhaps someone more knowledgable could give some tips here...

[giovannipizzi]

I agree that 10 GB is ok and we should try not the have a Vbox size over that (not including the .ova).

A few things we might do:

• remove some packages (we install ubuntu-desktop that is quite complete, but I'm sure half of the things are not useful). We can see the list of packages that are installed, and install only the needed ones (better to install what we need than to uninstall afterwards. Note: some gnome and similar packages are needed to have the GUI work correctly. But for instance we can remove things like LibreOffice?)
• we should run a sudo apt-get clean in a final 'cleaning-up' role (this frees up at least 500MB currently).
• ~.cache also is currently at 220 MB; we can clean up also /root/.cache even if this is small And probably there is still something that we can clean up (let's and them here and then work on it)

[giovannipizzi]

Currently, ubuntu-desktop has the following dependencies:

Depends: alsa-base, alsa-utils, anacron, at-spi2-core, bc, ca-certificates, 
checkbox-gui, dmz-cursor-theme, doc-base, fonts-dejavu-core, 
fonts-freefont-ttf, foomatic-db-compressed-ppds, genisoimage, 
ghostscript-x, gnome-menus, gnome-session-canberra, gstreamer1.0-alsa, 
gstreamer1.0-plugins-base-apps, gstreamer1.0-pulseaudio, gvfs-bin, 
inputattach, language-selector-gnome, libatk-adaptor, libnotify-bin, 
libsasl2-modules, lightdm, memtest86+, nautilus, notify-osd, openprinting-ppds, 
printer-driver-pnm2ppa, pulseaudio, rfkill, software-properties-gtk, 
ubuntu-artwork, ubuntu-drivers-common, ubuntu-release-upgrader-gtk, 
ubuntu-session, ubuntu-settings, ubuntu-sounds, unity, unity-control-center, 
unity-greeter, unity-settings-daemon, unzip, update-manager, 
update-notifier, wireless-tools, wpasupplicant, xdg-user-dirs, xdg-user-dirs-gtk, 
xdiagnose, xkb-data, xorg, yelp, zenity, zip

and the recommended packages (that are installed by default):

Recommends: a11y-profile-manager-indicator, acpi-support, 
activity-log-manager, aisleriot, app-install-data-partner, apport-gtk, 
avahi-autoipd, avahi-daemon, baobab, bluez, bluez-cups, branding-ubuntu, 
brltty, cheese, cups, cups-bsd, cups-client, cups-filters, deja-dup, eog, 
evince, example-content, file-roller, firefox, fonts-guru, fonts-kacst-one, 
fonts-khmeros-core, fonts-lao, fonts-liberation, fonts-lklug-sinhala, 
fonts-nanum, fonts-noto-cjk, fonts-sil-abyssinica, fonts-sil-padauk, 
fonts-takao-pgothic, fonts-thai-tlwg, fonts-tibetan-machine, fwupd, 
fwupdate, fwupdate-signed, gedit, gnome-accessibility-themes, 
gnome-bluetooth, gnome-calculator, gnome-calendar, gnome-disk-utility, 
gnome-font-viewer, gnome-keyring, gnome-mahjongg, gnome-mines, 
gnome-orca, gnome-power-manager, gnome-screensaver, gnome-screenshot, 
gnome-sudoku, gnome-system-log, gnome-system-monitor, gnome-terminal, 
gnupg-agent, gucharmap, gvfs-fuse, hplip, ibus, ibus-gtk, ibus-gtk3, 
ibus-table, im-config, kerneloops-daemon, laptop-detect, libgail-common, 
libnss-mdns, libpam-gnome-keyring, libproxy1-plugin-gsettings, 
libproxy1-plugin-networkmanager, libqt4-sql-sqlite, libreoffice-calc, 
libreoffice-gnome, libreoffice-impress, libreoffice-math, libreoffice-ogltrans, 
libreoffice-pdfimport, libreoffice-style-breeze, libreoffice-writer, 
libwmf0.2-7-gtk, mousetweaks, nautilus-sendto, nautilus-share, 
network-manager-gnome, network-manager-pptp-gnome, onboard, 
overlay-scrollbar-gtk2, pcmciautils, plymouth-theme-ubuntu-logo, 
policykit-desktop-privileges, ppp, pppconfig, pppoeconf, printer-driver-brlaser, 
printer-driver-c2esp, printer-driver-foo2zjs, printer-driver-min12xxw, 
printer-driver-ptouch, printer-driver-pxljr, printer-driver-sag-gdi, 
printer-driver-splix, pulseaudio-module-bluetooth, pulseaudio-module-x11, 
python3-aptdaemon.pkcompat, qt-at-spi, remmina, rhythmbox, seahorse, 
shotwell, simple-scan, snapd, sni-qt, speech-dispatcher, 
system-config-printer-gnome, thunderbird, thunderbird-gnome-support, 
totem, transmission-gtk, ttf-ancient-fonts-symbola, ttf-ubuntu-font-family, 
ubuntu-docs, ubuntu-software, unity-accessibility-profiles, 
unity-webapps-common, usb-creator-gtk, vino, whoopsie, xcursor-themes, 
xdg-utils, xterm, xul-ext-ubufox, zeitgeist-core, zeitgeist-datahub

[giovannipizzi]

I would probably leave all the necessary packages, and instead remove some of the recommended ones? Now that I look the list is pretty massive, maybe better to remove selectively what we know we don't want, to have the asnsible scripts more resilient to upgrade of ubuntu versions? Probably some of the things I would remove include:

• cups, cups-bsd, cups-client, cups-filters (we don't need to support printers)
• printer-driver-*
• fonts-* (maybe we just choose a few that are used by default)
• gnome-calendar
• gnome-font-viewer
• gnome-mahjongg, gnome-mines, gnome-sudoku, ... (and other games)
• libreoffice-* (unless we want to leave libreoffice-calc for making simple plots??)
• rhythmbox (we don't need music players)
• thunderbird, thunderbird-gnome-support
• ubuntu-docs

[giovannipizzi]

after running sudo apt-get remove cups cups-bsd cups-client cups-filters 'printer-driver-*' fonts-* gnome-calendar gnome-font-viewer gnome-mahjongg gnome-mines gnome-sudoku libreoffice-* rhythmbox thunderbird thunderbird-gnome-support ubuntu-docs followed by sudo apt-get autoremove we went down by another ~800MB. Note: in this case adapt the 'customisation' role to remove the two icons of libreoffice from the launcher.

Some of the other things listed probably can be removed but I don't know what they do and if they are essential. We should also check that everything still works... On the other hand, for some plotting libraries (even matplotlib) maybe it would be good to add a "minimal" latex installation? (this risks to be big, though)

[giovannipizzi]

Maybe we can also remove jmol from the list of installed packages - anyway now it does not work, unless we install java...

[giovannipizzi]

Another comment - we can remove the source code of codes, or at least remove the .o and similar files at the end.

A few notes:

• This should be done only in a final "cleanup" step before making the OVA - otherwise everytime one reruns ansible, it will have to recompile the codes
• for QE, do NOT do make clean - I just did it, but this cleans also the .x files...
• for QE the problem is not huge, but the size will add up when adding also other codes (see also #3)
• sometimes it's better to keep the source code in case someone wants to look into it? Otherwise we just clean all - what we can do is a cp --dereference ~/codes/pw-6.1/bin destdir to copy only the executables (the files and not the symlinks), then rm -r ~/codes/pw-6.1/* and finally mv destdir ~/codes/pw-6.1/bin to keep only the binaries? (again, as a final cleanup process)

[ltalirz]

Thanks for the hints!

A few comments:

• The way to do this in ansible is to notify a handler (handlers just run, when something changed, and only once at the very end). See cbe6dccfcc7f55c8a827eda504b375f0133dbb6b
• Is apt autoremove safe? Doesn't it remove all packages that no other packages depend on?
• Are you already working on this or should I start?

[giovannipizzi]

Ok thanks!

• I think anyway it's good to have a final 'apt clean' call in a cleanup phase/role (as somewhere the notification with be forgotten)
• instead of ~/.cache I would use the ANSIBLE HOME variable as done elsewhere
• autoremove should remove all packages that no other packages depend on AND that were not installed manually so it will do nothing if you never uninstalled anything. It's useful to remove what was installed as a dependency of something you uninstalled. So it should be safe in our case.

[giovannipizzi]

Interesting link (but very outdated! it's from 2008!) https://help.ubuntu.com/community/Diet%20Ubuntu

[ltalirz]

Regarding the removal of unnecessary packages (+autoremove): I'm not quite sure how to marry this with the 'idempotency' concept. If one does it just naively, then our apt install ubuntu-desktop will re-install those packages every time (I just checked).

So, it would seem to me that the way forward is to, instead, come up with a list of packages that we do need. Perhaps by installing ubuntu desktop, then removing unnecessary packages, then autoremove and then listing all installed packages?

Hm... I start thinking that we will just invite problems by trying to also manage all of these packages (then people don't find packages they are used to ...). autoclean + removing ~/.cache is fine, but perhaps we should let ubuntu decide what to install. Unless there is some 'selection' like ubuntu-desktop that better serves our needs.

[giovannipizzi]

Looks ok. I would then replace the apt install ubuntu-desktop with the explicit list of packages I list above, minus the ones I say we can remove. We can always keep removing stuff later. Thanks!

[ltalirz]

I wasted a few hours on this problem on Friday... it's not that trivial. One can install ubuntu-desktop with --no-install-recommends but then it also seems to skip the recommended packages of the required dependencies (which causes numerous problems, e.g. lightdm fails to start). In the slim-ubuntu-desktop branch, I've started adding these packages back in, but it's a bit of a pain because it's not easy to figure out which missing packages actually cause the problems. Also, this list of packages might change in the future in and I don't think we want to be forced to maintain it. Of course, instead of installing ubuntu-desktop one could also just take the list of packages required by ubuntu-desktop and install those directly. However, also this list may be subject to change.

I've added a question on askubuntu to see whether there is a maintainable way of achieving what we want.

[ltalirz]

Another possibility would be to switch to the LXDE - on top of Ubuntu or even on top of the lighter LUbuntu.

Currently there is no LUbuntu bento image, so LUbuntu is not an option for the moment.

Installing LXDE on top of Ubuntu works fine (just replace apt-get install ubuntu-desktop by apt-get install lxde lxde-common), and the image size after the common ansible tasks are

• ubuntu + ubuntu-desktop: 2.4GB
• ubuntu + lxde: 1.5 GB

However, the result does look a bit antiquated and would need some work... I don't think it's worth the trouble at the moment.

[ltalirz]

In summary:

To do:

• [x] rm -rf ~/.cache (421MB on 18.10RC1)
• [x] sudo rm -rf /root/.cache (4MB on 18.10RC1)
• [x] sudo apt-get clean (979MB on 18.10RC1)
• [x] sudo rm -rf /var/lib/apt/lists/* (178MB on 18.10RC1)

Not to do:

• remove source code of simulation codes (might be helpful)
• remove packages from ubuntu-desktop manually (destroys idempotency + can introduce problems) or try to hand-pick every package to install (tedious to maintain)
• switch to lighter LXDE/LUbuntu (looks outdated)

[giovannipizzi]

Is it worth trying lubuntu? https://www.ubuntu.com/download/flavours I don't know if 1) it's lighter 2) there are bento boxes or similar to start with

(or maybe replacing ubuntu-desktop with lxqt + additional needed packages if this does not become a huge list of things to install - see also https://www.tecmint.com/install-lxqt-desktop-in-ubuntu-fedora/)

[ltalirz]

Concerning lubuntu/lxde, see comment above. I think staying with the default ubuntu desktop is a good choice for the moment.

[giovannipizzi]

Ok, but note that

Lubuntu is a light, fast, and modern Ubuntu flavor using LXQt as its default desktop environment. Lubuntu used to use LXDE as its default desktop environment.

[ltalirz]

Ah sorry - I missed that. Opened #84 for this, so we can close this one.

To-do list completed in marvel-nccr/ansible-role-ubuntu-desktop@73d92233cce43100399c1c1c104ea9141a6957f5