Flash and codecs
Adobe Flash and MPEG-4 codecs are not Free Software and may have some legal issues in some countries, so they are not installed by default, unless you click that checkbox on the installer.
Lighter alternatives
For a single core computer, you better go for a lighter Ubuntu variant like Lubuntu or Xubuntu. Single core, no hyperthreading CPUs are old. Yes, they are. No, seriously.
The RAM usage
Anyways, please make sure Ubuntu is actually actively using 96% of your RAM. If you run the command free -m, take a look at the second number on the second line, the one starting with -/+ buffers/cache. That's actually the free unused RAM. Ubuntu makes usage of otherwise unused RAM memory to cache i/o operations and recently opened programs, but it's not a true RAM usage.
About the 164 tasks
On my desktop, there's now 204 tasks as reported by top. However, 77 of them are actually kernel-space threads, not processes. As for the rest, please understand that:
Ubuntu is a multiuser, multitask, layered operative system. There are system daemons exposing interfaces to users via a intercommunication system, that must control the permissions: what users can and cannot do. So that's the reason because there's a lot of processes there, eating your RAM. But they're just sleeping. Not doing anything.
Most components are built upon the reuse premise. For that reason, most Ubuntu tasks must run several processes to achieve a goal.
For example, now I have 6 Network Manager related processes running, and that's only for managing the network:
- 1 main process that does nothing, just forks launching what is needed.
- 1 process to handle DHCP, because it's reusing
dhclient.
- 1 process to handle DNS, because it's reusing
dnsmasq.
- 1 process to handle the VPN connections, that basically put together all the neccessary options to launch...
- 1 process to handle the opened VPN connection, since it's reusing
openvpn.
- 1 process to show the user interface, that icon on the top bar that reacts when I press on it.
From that 6 processes, no one is doing anything, they are slept. So, they won't eat your CPU, but they will probably ear your RAM.
Everything comes with a price, and on the software world, if you lower the RAM consumption, you put up the I/O and CPU consumption, and viceversa.
Of course, on a so complex task like Ubuntu does, manage all your computer enjoyment, there's a lot of room for improvement. The graphical architecture (Xorg, compiz, etc.) is too complex, and Unity probably launches too much daemons to provide search on-the-go but not-so-useful functionality.
