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power management

Linux Ramback: Use a Terabyte of RAM

An experimental new design for Linux's virtual memory system would turn a large amount of system RAM into a fast RAM disk with automatic sync to magnetic media. Most servers comes with 2-16 GB ram installed but not with a terabyte of installed memory (for 1TB+ ram go with IBM / Sun E25k server line). There is a new kernel patch called Ramback:

Ramback is a new virtual device with the ability to back a ramdisk by a real disk, obtaining the performance level of a ramdisk but with the data durability of a hard disk. To work this magic, ramback needs a little help from a UPS. In a typical test, ramback reduced a 25 second file operation to under one second including sync. Even greater gains are possible for seek-intensive applications. The difference between ramback and an ordinary ramdisk is: when the machine powers down the data does not vanish because it is continuously saved to backing store. When line power returns, the backing store repopulates the ramdisk while allowing application io to proceed concurrently. Once fully populated, a little green light winks on and file operations once again run at ramdisk speed.

However, this solution depends upon UPS:

If line power goes out while ramback is running, the UPS kicks in and a power management script switches the driver from writeback to writethrough mode. Ramback proceeds to save all remaining dirty data while forcing each new application write through to backing store immediately.

Ubuntu Tweak Software to Change Hidden Desktop Settings

Generally, I recommend using gconf-editor ~ a tool used for editing the GConf configuration database (Gnome settings). You can always edit configuration files. Many new Linux users find it difficult to use both gconf-editor and text files.

To make your life easier and to save time try out new Ubuntu Tweak software. It is designed to configure Ubuntu easily using GUI tools. It provided many useful Ubuntu desktop and system tweaking options such as:
=> View Basic System Information
=> GNOME Session Control
=> Show/Hide and Change Splash screen
=> Show/Hide desktop icons or Mounted Volumes
=> Show/Hide/Rename Computer, Home, Trash icon or Network icon
=> Tweak Metacity Window Manager's Style and Behavior
=> Compiz Fusion settings, Screen Edge Settings, Window Effects Settings, Menu Effect Settins
=> GNOME Panel Settings
=> Nautilus Settings
=> Advanced Power Management Settings
=> System Security Settings and much more

Quick Installation

$ cd /tmp; wget http://ubuntu-tweak.googlecode.com/files/ubuntu-tweak_0.2.4-ubuntu2_all.deb
$ sudo dpkg -i ubuntu-tweak_0.2.4-ubuntu2_all.deb
$ ubuntu-tweak &

Ubuntu Tweak to Change Desktop Settings
(Fig. 01: Ubuntu Tweak in Action)

Bruce Byfield has published an interesting article on Linux.com:

For years, discerning Windows users have relied on Tweak UI, a semi-official Microsoft program for system settings not available on the default desktop. Now, in the same tradition and with something of the same name, Ubuntu Tweak (UT) offers the same advantage to Ubuntu users. Currently at version 0.2.4, for now UT is limited to features for GNOME and focuses mainly on changing default desktop and system behavior and how GNOME interacts with your hardware, but this small feature set is more than enough for proof of concept.

Download Ubuntu Tweak Software

=> Grab Ubuntu Tweak here (via Linux.com).

Does Ubuntu Linux kill / shorten hard disk life?

I got lots of emails asking about Ubuntu Linux and hard disk issue. Does it really shorten hard disk life?


Unfortunately, some news and blogs reported news wrongly. Ubuntu doesn't touch your hard drive power management settings by default. In almost all cases, it's more likely to be your BIOS or the firmware on your hard drive (source).

Check out this official bug report for more information. On a related note, always consider backing up hard disk / data on regular basis.