Netrunner 13.06 Enigma Tweaks for the Memory Deprived PC

by Dietrich Schmitz

I've been living with Netrunner 13.06 Enigma for about a week now and am still quite happy with it.

Yet, I am not satisfied to just use any Distro with its 'out of the box' setting for long before the urge sets in to make changes.

Mostly, for my purposes, I want the ram footprint of the GUI to be as small as it can possibly be. (Image credit: smithsonianmag.com)

Where KDE is concerned, while it does weigh in in the 400MB+ range at start-up the Acer Aspire One D260 in default configuration is quite acceptable speed-wise.  I half-expected that would not be the case and was happy to know the system was carrying the weight of a full KDE Plasma Workspace implementation nicely.

So, the lust to tweak set in and here's what I did.

Unneeded Services

I disabled the following services

Akonadi (set StartServer=false in ~/.config/akonadi/akonadiserverrc)
cups and cups-browserd (sudo update-rc.d -f cups remove && update-rc.d -f cups-browserd remove)
krunner
Added the below contents to file ~/.kde/share/autostart/krunner.desktop

[Desktop Entry]
Exec=krunner
Hidden=true
X-DBUS-StartupType=none
Name=Command Runner
Type=Service
X-KDE-StartupNotify=false
OnlyShowIn=KDE;
X-KDE-autostart-phase=1

klipper (sudo apt-get purge klipper)
nepomuk (off by default; set autostart=false in ~/.kde/share/config/nepomukserverrc)

3D Effects

System Settings, Workspace Appearance, Desktop Effect, uncheck 'Enable Desktop Effects at Startup' and on the Advanced tab, switched from OpenGL to xrender.

Other Services

In system settings, Advanced, Service Manager, I unchecked and stopped:

DNS-SD
Drive Ejector (my Netbook has no CD drive)
Free Space Notifier (I've never run out of disk space)
Nepomuk Search Module
Remote URL Change Notifier
Wacom Tablet (don't have one)
Write Daemon

System Settings, Desktop Appearance, Widget Style, Configure, Animations, I unchecked 'Enable Animations'.

Preload

Preload uses caching algorithms to intelligently preload software based on your user habits.  I installed with:

sudo apt-get install preload

zram

I've been using zram for several days.  I will tell you that this change alone will make a big change in the speed of any PC -- it doesn't matter how much ram it has.  In fact, it's going to be present in the Kernel 3.11 as zswap, but currently, it exists if you are using a Linux kernel 3.2 or greater as zram.  Users of Netrunner get a 3.8 kernel with the 'bonus' of an enhanced LZO compression library.

The command to install:

sudo apt-get install zram-config.

There isn't anything else you need to configure for zram -- it is now mapped and loaded as a kernel module (zram.ko) to two block swap devices with the name /dev/zram[n] where n is the core of your PC.  In my case with the Atom N450, it's /dev/zram0 and /dev/zram1.
If you would like to see your zram swap activity, I would suggest installing ncurses-based 'glances' (sudo apt-get install glances).

So, that's it.  Now things are absolutely 'honkin' fast.

P.S. those using Fedora will find zram installables here.

Good Luck.

-- Dietrich

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Get Your PC's MoJo Going with zRAM

by Dietrich Schmitz

Using a Netbook has both advantages and disadvantages.  Mine, an Acer Aspire One D260 (Intel Atom N450) came with 1GB DDR2 ram.  I added another 1GB to bring it up to 2GB ram total. (Image credit: wallpaperswa.com)

Overall, using the Netbook has been a great value proposition.  Because Linux does so well with limited ram, some Distros better than others, I've managed to get along just fine.

Very recently, I made a switch from Fedora 19 to Netrunner 13.06 Enigma and have been doing various tweaks of the Desktop to configure it to my liking.

Very little in fact, needed to be changed from the start, which speaks well for KDE and Blue Systems.  Blue Systems, in particular, have done a superb job in putting together Enigma.

By chance today, I came upon a feature which landed in the Linux kernel 3.2, called zRAM.

If your PC has 2GB ram or less, then zRAM is for you.  In Linux kernel 3.8, a new LZO compression library update is present that in testing shows roughly double speed improvements for compression/decompression.

zRAM uses LZO to create compressed swap space in RAM.

Beyond the install step, there's no special configuration required -- zRAM loads on boot and sets itself up in RAM with a higher priority than your default swap partition.  The result is that zRAM is engaged first, if full, then your SDD/HDD partition will do the more I/O-intensive swapping which, of course, is vastly slower.

I've been using zRAM all day and must say it was well worth the trouble of installing.  The speed improvement is pronounced.  And it just so happens Enigma, released this past Friday (July 5) uses a 3.8 kernel.  So the newest LZO compression library is installed also.

Using Chrome typically is memory-instensive and if I open 6 or more tabs, I notice swapping begins to slow things down.  I usually am careful about closing unneeded tabs just as soon as I am done with them to avoid hitting that memory maxed-out wall where swapping starts to kick in.

Now, I have not hit the 'wall' once since installing zRAM and everything snaps to screen as though this machine was equipped with 4GB of ram.  I kid you not.

So, if you have a machine with 2GB ram or less, I strongly recommend you give zRAM a try, and especially if you are using Linux kernel 3.8 or greater.

There you have it!

-- Dietrich

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