posted by Howard Fosdick on Tue 1st Mar 2011 16:39 UTC
IconUbuntu Linux has millions of fans. What's not to like? A free operating system with ten thousand free applications, websites covering everything you might ever want to know, tutorials, active forums, and more. Yet for all these benefits, situations pop up when you want a faster, lighter operating system. Perhaps you have an older computer, or maybe a netbook or a mobile device. Wouldn't it be great to have a lightweight Ubuntu? That day has finally arrived. Lubuntu offers a way to stay in the Ubuntu family -- with a product that performs better and uses fewer resources.

This article details how Lubuntu differs from Ubuntu. It also compares Lubuntu to other lightweight Linuxes. It focuses on Lubuntu 10.04, which is based on Ubuntu's 10.04 Long Term Support release.  (Lubuntu 10.10 is the latest release, with 11.04 due out at the end of April.)  Sample screenshots follow the article.

The Criteria

Before we start, here's where I'm coming from. As per previous articles in this series at OS News, my interest in lightweight operating systems stems from my activity in refurbishing computers for charity. The best software for this purpose is:
  • Resource light --  charitable donations are between five and ten years old
  • Easy to use --  recipients use donations with little or no training
  • Easy to install and configure --  volunteer labor doesn't like complexity or wasting time
  • Free --  charities don't have money to buy software
  • Open source --  commercial licensing agreements unduely restrict install and distribution procedures
  • Good support -- this is why I favor the LTS (Long Term Support) releases in the Ubuntu family
In future OS News articles, I'll review competing low-end distros like Puppy Linux and Damn Small Linux. All my reviews judge by these criteria.

How Lubuntu Differs From Ubuntu

Lubuntu changes Ubuntu in three major respects to become a faster, lighter system:

1. The LXDE graphical interface replaces GNOME

2. Default daemons and services are paired down to the minimum

3. Faster, lighter default applications replace Ubuntu's default applications

Let's discuss each of these techniques.

LXDE -- The graphical user interface or GUI is the most resource-intense component of consumer operating systems. Lubuntu tackles this challenge head-on by using as its default the Lightweight X11 Desktop Environment or LXDE. LXDE replaces Ubuntu's easy to use but resource-hungry GNOME.

LXDE uses less memory than GNOME for typical workloads. Its twenty or so components are loosely integrated, so they can run independent of one another, saving resources. The Openbox window manager is especially important from the resource standpoint. This comparison of popular window managers shows that Openbox yields a full range of features at a very modest resource cost.

From the usability standpoint, LXDE is less sophisticated than Ubuntu's GNOME desktop. But it's nearly as easy to use. You can still add desktop icons, panels, panel applets, and the like. And you can quickly customize your desktop. The first time I used Lubuntu, it only took me a few minutes to alter its default interface to my preferred style.

Minimal Daemons -- You can configure either Lubuntu or Ubuntu to start up whatever daemons or services you prefer. By default, Lubuntu starts many fewer than Ubuntu.  You can view the Lubuntu startup applications by entering:

Start -> Preferences -> Desktop Session Settings -> Automatically Started Applications (Tab)

The equivalent under Ubuntu is:

System -> Preferences -> Startup Applications -> Startup Programs (Tab)

In older Ubuntu releases you can also look under the "Services" panel:

System -> Administration -> Services

By pairing down Ubuntu's default startup programs, Lubuntu boots lean and mean. You can always add additional services if you need them by navigating to the panels referenced here.

Lighter Applications --  While Lubuntu uses less memory than Ubuntu at idle, where you really see its utility is when you open many applications concurrently. Since the apps require less memory than their Ubuntu equivalents, the cumulative effect is a faster, more performant system.

I especially like the file manager, PCMan, an LXDE component. I've found it visibly faster than Ubuntu's Nautilus on older computers, with their limited memory and slow PATA/IDE hard drives.

GNOME Office replaces Ubuntu's OpenOffice, so Lubuntu comes with AbiWord and Gnumeric, instead of OpenOffice Writer and Calc. Lubuntu bundles no equivalent to Ubuntu's presentation tool, OpenOffice Impress. Lubuntu also includes the handy Osmo personal organizer and calendar.

The theme of lighter apps runs throughout Lubuntu -- Leafpad replaces Ubuntu's Gedit, LXTerminal is included instead of GNOME Terminal, Sylpheed handles email instead of Evolution, and the Xfce4 Taskmanager tracks performance instead of Ubuntu's System Monitor.

In a move that has inspired controversy in web forums, Lubuntu uses Chromium as its default browser instead of Firefox. To me Chromium seems a bit faster than Firefox on low-end computers. Its clean, simple, intuitive interface certainly fits the Lubuntu emphasis on ease of use.

Of course, if you prefer Firefox or any other application that is not bundled with Lubuntu, you can easily install it. Lubuntu uses the same Synaptic Package Manager and accesses all the same software repositories as Ubuntu. So you could start out by installing Lubuntu as a small, efficient operating system, then cherry-pick critical Ubuntu apps you require from the shared repositories. You'll get the quick system you want without the overhead of the applications and daemons you don't need.

Resource Use

Lubuntu's goal is efficient resource use. So let's measure it.

Lubuntu bundles the Xfce4 Taskmanager for measuring resource use, instead of Ubuntu's System Monitor. Linux line commands like free, top, vmstat, and df can also be handy.

Let's look at some numbers:

Download File Size:
Disk Install:
Memory Use:

Ubuntu 10.04
686 m
3 - 5 g
110 - 250 m
Lubuntu 10.04
521 m
1 - 2 g
60 - 130 m
Puppy 5.1
130 m
500 - 1000 m *
30 - 120 m
Damn Small Linux 4.4.10
50 m
200 - 300 m *
25 - 100 m
* For a "full install."  A "frugal install" requires about the same space as the download.  All measurements are by the author.

The size of the disk install will vary, depending on the apps you add to the base system. In rough terms it's fair to say that an Lubuntu install consumes one-third to one-half of the disk space used by Ubuntu. Want an exact number? It varies by user, product release, and what you add to the base install.  The only way to get exact numbers is to measure disk footprints for your own systems.

Lubuntu generally uses about half the memory of Ubuntu. But be careful again: memory measurements vary because we're talking the size of the operating system plus loaded apps (we exclude the buffers or cache used by the OS). Obviously this number could be all over the map depending on the applications you start. And, how you use them. The numbers I list above reflect my own typical use of these systems. Your numbers will vary depending on your use of your computer.

If you collect your own measurements, you'll immediately find that certain apps eat up way more memory than others. For example, browsers are famously ram-hungry. The more tabs you open, the more ram they eat. So if you compare memory use between Linux distributions, open functionally-equivalent apps (and the same number of tabs in the browser) from a cold startup.

In my experience the upper range of real memory used by Lubuntu corresponds to the lower end of what Ubuntu consumes. Almost anyone will find that Lubuntu uses dramatically less memory than Ubuntu.

I added Puppy 5 to the chart as a directly competing product from outside of the Ubuntu family. I found Lubuntu's memory use to be roughly similar to Puppy's, though Puppy uses less at initial load and at idle. Puppy has a much smaller download file and installed disk footprint.

I also added Damn Small Linux to the chart to bracket the numbers on the low end in the same way that Ubuntu brackets them on the high end. Comparing Lubuntu to DSL is really like comparing apples to oranges. DSL uses way fewer resources. But it bundles fewer apps and doesn't offer anywhere near the same ease of use as Lubuntu. DSL is a great tool for hobbyists and IT professionals, but it isn't suitable for untutored computer users like Lubuntu.

My Experiences

I've had Ubuntu 8.x and 9.x running on five P-III's and four P-IV's since those releases came out. Ubuntu 10.04 disappointed me on this older equipment. Due to video issues it didn't install, out of the box, on any of the five P-III's. It installed successfully on all the P-IV's but one, a Gateway Profile 4 All-In-One PC. I eventually got Ubuntu 10.04 to run on all these computers but it took some geeky tweaks. OS News readers could certainly implement these techniques. But they are probably beyond skill of the average computer consumer.

Lubuntu 10.04 installed right out-of-the-box on the three P-III's I still had access to. No tweaking required. It also ran immediately on all of the P-IV's, including the Gateway Profile 4.

I conclude that while Ubuntu runs great on P-IV's, with version 10.04, it finally leaves P-III's behind.  This makes sense because P-IV's have been out since 2000 and P-III's stopped production in 2003.  Lubuntu appears to pick up the slack for P-III's and may be a good alternative. Lubuntu will run on systems with down to 128M of memory, but to install it from Live CD you need at least 160M. (See the system requirements for details.)

I've really been impressed by Lubuntu's snappy responsiveness on older computers. The contrast to Ubuntu is noticeable. The personal rule of thumb I've developed about when to use Lubuntu versus Ubuntu is this:

  • For P-IV's or better with 512 M or more of DDR-1 memory, go with Ubuntu
  • For P-IV's with lesser memory, and all P-III's, go with Lubuntu

If you have an old machine in your attic or basement, Lubuntu is a great tool to revive it and make it useful again. In my tests Lubuntu provided a nice, responsive system on all the old computers listed below. Machines like these have little to no resale value and you can often pick up them up for free from friends, family, co-workers, Freecycle, or Craigslist. Pretty amazing that Lubuntu makes them all useful, when you think about it!

CPU Speed:

550 mhz
512 m (PC-100)
20 g (PATA/IDE)
933 mhz
256 m (PC-133)
40 g (PATA/IDE)
1.5 ghz
512 m (PC-133)
40 g (PATA/IDE)
2.4 ghz
768 m (DDR-1)
160 g (PATA/IDE)
2.6 ghz
1 g (DDR-1)
120 g (PATA/IDE)

From the standpoint of charitable work, machines like these are valuable to those who have no computer otherwise. (One in four Americans do not own a computer.) They also make good secondary machines for large families that have more kids than computers. I know IT professionals who keep their old P-IV around as an emergency backup if their current computer fails.

Lubuntu fulfills an important role in the PC ecosystem. While these computers have virtually no resale value they still provide value if placed and used appropriately.  If you have computer up to ten years old you don't use, please donate it to a charity like FreeGeek that will reuse it. Recyclers will only destroy it, then recycle the raw materials.

Comparison to other Lightweight Linuxes

Some web sites promote Xubuntu as a light alternative to Ubuntu. Xubuntu uses the XFCE interface instead of GNOME and it bundles lighter apps than Ubuntu.

During the 8.x and 9.x releases I ran several benchmarks pitting Xubuntu against Ubuntu. While Xubuntu generally used less memory than Ubuntu I wouldn't characterize the difference as significant. Xubuntu's memory advantage was small enough -- usually 0 to 20 m -- that I wrote off Xubuntu as a tool to revive older systems with too little memory to run Ubuntu.

This Linux Magazine article comparing Lubuntu, Xubuntu, and Ubuntu reached the same conclusion.  The Wikipedia article on Xubuntu summarizes the situation by stating that "Testing has concluded that Xubuntu 9.10 beta's RAM usage actually is greater than Ubuntu's 9.10 beta with GNOME."  So while Xubuntu is an excellent system, it didn't contribute towards my goal of making computers useful that are too resource-limited to run Ubuntu.

U-lite is another possibility. Like Lubuntu, U-lite is based on Ubuntu. It employs LXDE and bundles lightweight applications into the base system. I didn't test U-lite mainly because there appears little possibility that it will become an official member of the Ubuntu family. The project was originally called "Ubuntulite" but changed its name following a communication from Canonical Ltd. that the name violated Ubuntu trademarks. In contrast, Mark Shuttleworth, Canonical's founder, personally invited the Lubuntu project to start up. The prospects appear excellent for Lubuntu to become an official member of the Ubuntu family soon. (For example, you can already mark your question as pertaining to Lubuntu in the official Ubuntu forum.) U-lite may be an excellent distro but it fell out of scope for this project.

Puppy is an innovative light distro that consistently places among the top dozen distros according to the popularity rankings at Distrowatch.  Puppy automatically loads completely into memory, and runs solely from there, on any computer having 256 M or more. This eliminates slow disk and CD/DVD access and speeds system performance.

Puppy's resource consumption is less than or equal to Lubuntu's, as shown in the chart. Puppy achieves all this with ease of use I've found sufficient for end users (as long as the system has been installed and configured for them). I'll review Puppy next month.

From the perspective of computer refurbishing, both Lubuntu and Puppy are great candidates. It's nice to have choices!

Older Computers?

One question I have about Lubuntu is whether it will run on computers under 500 mhz that still meet its system requirements. This encompasses Pentium II's, early Celerons, and even some Pentium I's.

Competing distros take specific measures to support these older machines that Lubuntu does not. For example, Puppy supports a "retro kernel" release in parallel for each new version. You can run Puppy with either the retro kernel or a current kernel. Damn Small Linux still uses the 2.4 kernel and offers the SYSLINUX boot loader for systems that can not boot ISOLINUX. 

In the worse case, if the current release of Puppy or DSL won't boot on your old computer, you can go back and try older releases through five or six years of product evolution. I've sometimes had to resort to this to pick up support for older devices. You can't do this with Lubuntu. It's new and was first released in 2010. To my knowledge, it's not specifically tested on old computers that it could, theoretically, run on from the standpoint of system requirements.

What this means is that there are really two kinds of lightweight Linux distributions. Some specifically support older computers, while others offer current software for reasonably current machines that just happen to be resource-light. I suspect that Lubuntu fits into the latter category.

If any readers have tried Lubuntu on sub-500 mhz computers please share your experiences with us by posting a comment.  Did Lubuntu boot without tweaking? Did it recognize your old devices?  Please post experiences with Lubuntu on netbooks, too. I had only a single netbook to try it on and it worked fine. Thanks for your feedback.

Ubuntu Means "Change" in Bantu

Does "Ubuntu" mean "change" in Bantu? Well, actually no. Ubuntu is named for the south African concept of "humanity towards others."

But in terms of operating system compatibility, Ubuntu does mean Change. One of the Ubuntu family's big advantages is that it quickly capitalizes on new technology. These are fast-moving distros. The downsides are occasional incompatibility or disruptive change across releases.

In the last two years, the Ubuntu family has moved from the GRUB boot loader to GRUB 2, to continually changing networking management tools, to eliminating the xorg.conf configuration file and moving to RandR for video. Lately I've heard they may replace GDM with LightDM, move to more regular updates, replace with Wayland, switch the user interface from GNOME to Unity, and replace OpenOffice with LibreOffice. 

These are changes to Ubuntu, not Lubuntu. But Lubuntu follows Ubuntu and this philosophy of rapid change is fundamental to the Ubuntu family.

So consider your needs carefully when evaluating Lubuntu.  Do you need rapid updates and improvements? The Ubuntu family does a superior job in providing them. Or do you crave stability and backward compatibility? In this case you may find Ubuntu's constant push for new technology and features annoying or burdensome.

Lubuntu Is a Winner

Lubuntu successfully extends the Ubuntu family to limited-resource computers. I love its responsiveness on five to ten year old machines! The Lubuntu team has clearly done an excellent job in figuring out how to preconfigure a leaner, meaner Ubuntu.

While Lubuntu is a faster, lighter alternative to Ubuntu, you still get all the important Ubuntu benefits -- the thousands of downloadable applications, the forums, the helpful websites, the wikis, and more. You can get the best of both worlds by installing Lubuntu, then adding any extra applications you need from the Ubuntu software repositories.

If you seek a resource-light, well-supported Linux, Lubuntu could be your solution.

- - - - - - - - - - - - - - - - - - - - - -
Howard Fosdick (President, FCI) is an independent consultant who specializes in databases and operating systems. His hobby is computer refurbishing as a form of social work and environmental contribution. You can reach him at contactfci at the domain name of sbcglobal (period) net.

Lubuntu Links:

Wikipedia article
Another Review

Previous Articles on Computer Refurbishing

Smart Reuse with Open Source
How refurbishing defeats planned obsolescence
Scandal: Most "Recycled" Computers Are Not Recycled
What really happens to many "recycled" computers?
How to Revitalize Mature Computers Overview of how to refurbish mature computers
How to Secure Windows
A step-by-step procedure to secure Windows 
How to Tune Up Windows
How to tune Windows (any version)
How Microsoft Missed The Next Big Thing
How Microsoft missed the boat when it comes to the exploding popularity of small portable devices
How to Run Multiple Operating Systems
Describes and contrasts techniques to running multiple operating systems on a single computer

Lubuntu 10.04 Screenshots

The Basic Screen

The initial Lubuntu desktop has no icons. Like Windows, the system menu always starts from the lower left-hand corner of the screen. (With LXDE -- unlike XFCE or JWM -- you can't right-click anywhere you like to bring up the menu.) This screenshot shows the Accessories bundled with Lubuntu:

The Basic Desktop

Memory Use is Low

In this example I've opened mtPaint, AbiWord, Gnumeric, the Xfce4 Taskmanager, and the Chromium browser with three active tabs. Total memory use: 114m. Wow!

Low Memory Use

The File Manager

The PCMan file manager replaces Ubuntu's Nautilus. I've found it runs visibly faster on slow computers. PCMan is an LXDE component. By default Lubuntu dynamically mounts all partitions on all disks. This is consistent with Lubuntu's excellent ease of use.

PCManFM File Manager

Monitoring System Resources

The Xfce4 Taskmanager is a comprehensive but easy-to-use tool for managing system resources on a low-end box. It replaces Ubuntu's System Monitor.

Xfce4 Taskmanager

Synaptic Package Manager

Lubuntu uses the same Synaptic Package Manager as Ubuntu. Here I am searching Synaptic while trying to figure out how to take screenshots by looking for an appropriate package to install, since none is bundled with Lubuntu. Turns out I didn't need to download anything. Lubuntu has the scrot line command. I used this command to take all the screenshots you see here, with a delay of 10 seconds and the top quality of 100%:  scrot -d 10 -q 100 -u

Synaptic Package Manager
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