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Extend the life of your SSD on linux

February 9th, 2014 2 comments

This past year I purchased a laptop that came with two drives, a small 24GB SSD and a larger 1TB HDD. My configuration has placed the root filesystem (i.e. /) on the SSD and my home directory (i.e. /home) on the HDD so that I benefit from very fast system booting and application loading but still have loads of space for my personal files. The only downside to this configuration is that linux is sometimes not the best at ensuring your SSD lives a long life.

Unlike HDDs, SSDs have a finite number of write operations before they are guaranteed to fail (although you could argue HDDs aren’t all that great either…). Quite a few linux distributions have not yet been updated to detect and configure SSDs in such a way as to extend their life. Luckily for us it isn’t all that difficult to make the changes ourselves.

Change #1 – noatime

The first change that I do is to configure my system so that it no longer updates each files access time on the SSD partition. By default Linux records information about when files were created and last modified as well as when it was last accessed. There is a cost associated with recording the last access time and including this option can not only significantly reduce the number of writes to the drive but also give you a slight performance improvement as well. Note that if you care about access times (for example if you like to perform filesystem audits or something like that) then obviously disabling this may not be an option for you.

Open /etc/fstab as root. For example I used nano so I ran:

sudo nano /etc/fstab

Find the SSD partition(s) (remember mine is just the root, /, partition) and add noatime to the mounting options:

UUID=<some hex string> /               ext4    noatime,errors=remount-ro

Change #2 – discard

UPDATE: Starting with 14.04 you no longer need to add discard to your fstab file. It is now handled automatically for you through a different system mechanism.

TRIM is a technology that allows a filesystem to immediately notify the SSD when a file is deleted so that it can more efficiently manage the underlying storage and improve the lifespan of the drive. Not all filesystems support TRIM but if you are like most people and use ext4 then you can safely enable this feature. Note that some people have actually had drastic write performance decreases when enabling this option but personally I’d rather have that than a dead drive.

To enable TRIM support start by again opening /etc/fstab as root and find the SSD partition(s). This time add discard to the mounting options:

UUID=<some hex string> /               ext4    noatime,errors=remount-ro,discard

Change #3 – tmpfs

If you have enough RAM you can also dedicate some of it to mounting specific partitions via tmpfs. Tmpfs essentially makes a fake hard drive, known as a RAM disk, that exists only in your computer’s RAM memory while it is running. You could use this to store commonly written to temporary filesystems like /tmp or log file locations such as /var/logs.

This has a number of consequences. For one anything that gets written to tmpfs will not be there the second you restart or turn the computer off – it never gets written back to a real hard drive. This means that while you can save your SSD all of those log file writes you also won’t be able to debug a problem using those log files on a computer crash or something of the like. Also being a RAM disk means that it will slowly(?) eat up your RAM growing larger and larger the more you write to it between restarts. There are options for putting limits on how large a tmpfs partition can grow but I’ll leave you to search for those.

To set this up open /etc/fstab as root. This time add new tmpfs lines using the following format:

tmpfs   /tmp    tmpfs   defaults  0       0

You can lock it down even more by adding some additional options like noexec (disallows execution of binaries on the filesystem) and nosuid (block the operation of suid, and sgid bits). Some other locations you may consider adding are /var/log, /var/cache/apt etc. Please read up on each of these before applying them as YMMV.

Categories: Hardware, Tyler B Tags: , , , , ,

Change the default sort order in Nautilus

February 9th, 2014 1 comment

The default sort order in Nautilus has been changed to sorting alphabetically by name and the option to change this seems to be broken. For example I prefer my files to be sorted by type so I ran

dconf-editor

and browsed to org/gnome/nautilus/preferences. From there you should be able to change the value by using the drop down:

 

Seems easy enough

Seems easy enough

Unfortunately the only option available is modification time. Once you change it to that you can’t even go back to name. This also appears to be a problem when trying to set the value using the command line interface like this:

dconf write /org/gnome/nautilus/preferences/default-sort-order type

I received an “error: 0-4:unknown keyword” message when I tried to run that.

Thanks to the folks over on the Ask Ubuntu forum I was finally able to get it to change by issuing this command instead:

gsettings set org.gnome.nautilus.preferences default-sort-order type

where type could be swapped out for whatever you prefer it to be ordered by.

Great Success!

Great Success!

CoreGTK

January 28th, 2014 2 comments

A while back I made it my goal to put together an open source project as my way of contributing back to the community. Well fast forward a couple of months and my hobby project is finally ready to be shown the light of day. I give you… CoreGTK

CoreGTK is an Objective-C binding for the GTK+ library which wraps all objects descending from GtkWidget (plus a few others here and there). Like other “core” Objective-C libraries it is designed to be a very thin wrapper, so that anyone familiar with the C version of GTK+ should be able to pick it up easily.

However the real goal of CoreGTK is not to replace the C implementation for every day use but instead to allow developers to more easily code GTK+ interfaces using Objective-C. This could be especially useful if a developer already has a program, say one they are developing for the Mac, and they want to port it to Linux or Windows. With a little bit of MVC a savvy developer would only need to re-write the GUI portion of their application in CoreGTK.

So what does a CoreGTK application look like? Pretty much like a normal Objective-C program:

/*
 * Objective-C imports
 */
#import <Foundation/Foundation.h>
#import "CGTK.h"
#import "CGTKButton.h"
#import "CGTKSignalConnector.h"
#import "CGTKWindow.h"

/*
 * C imports
 */
#import <gtk/gtk.h>

@interface HelloWorld : NSObject
/* This is a callback function. The data arguments are ignored
 * in this example. More callbacks below. */
+(void)hello;

/* Another callback */
+(void)destroy;
@end

@implementation HelloWorld
int main(int argc, char *argv[])
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    /* We could use also CGTKWidget here instead */
    CGTKWindow *window;
    CGTKButton *button;

    /* This is called in all GTK applications. Arguments are parsed
    * from the command line and are returned to the application. */
    [CGTK autoInitWithArgc:argc andArgv:argv];

    /* Create a new window */
    window = [[CGTKWindow alloc] initWithGtkWindowType:GTK_WINDOW_TOPLEVEL];

    /* Here we connect the "destroy" event to a signal handler in 
     * the HelloWorld class */
    [CGTKSignalConnector connectGpointer:[window WIDGET] 
        withSignal:@"destroy" toTarget:[HelloWorld class] 
        withSelector:@selector(destroy) andData:NULL];

    /* Sets the border width of the window */
    [window setBorderWidth: [NSNumber numberWithInt:10]];

    /* Creates a new button with the label "Hello World" */
    button = [[CGTKButton alloc] initWithLabel:@"Hello World"];

    /* When the button receives the "clicked" signal, it will call the
     * function hello() in the HelloWorld class (below) */
    [CGTKSignalConnector connectGpointer:[button WIDGET] 
        withSignal:@"clicked" toTarget:[HelloWorld class] 
        withSelector:@selector(hello) andData:NULL];

    /* This packs the button into the window (a gtk container) */
    [window add:button];

    /* The final step is to display this newly created widget */
    [button show];

    /* and the window */
    [window show];

    /* All GTK applications must have a [CGTK main] call. Control ends here
     * and waits for an event to occur (like a key press or
     * mouse event). */
    [CGTK main];

    [pool release];

    return 0;
}

+(void)hello
{
    NSLog(@"Hello World");
}

+(void)destroy
{
    [CGTK mainQuit];
}
@end
Hello World in action

Hello World in action

And because Objective-C is completely compatible with regular old C code there is nothing stopping you from simply extracting the GTK+ objects and using them like normal.

// Use it as an Objective-C CoreGTK object!
CGTKWindow *cWindow = [[CGTKWindow alloc] 
    initWithGtkWindowType:GTK_WINDOW_TOPLEVEL];

// Or as a C GTK+ window!
GtkWindow *gWindow = [cWindow WINDOW];

// Or even as a C GtkWidget!
GtkWidget *gWidget = [cWindow WIDGET];

// This...
[cWindow show];

// ...is the same as this:
gtk_widget_show([cWindow WIDGET]);

You can even use a UI builder like GLADE, import the XML and wire up the signals to Objective-C instance and class methods.

CGTKBuilder *builder = [[CGTKBuilder alloc] init];
if(![builder addFromFile:@"test.glade"])
{
    NSLog(@"Error loading GUI file");
    return 1;
}

[CGTKBuilder setDebug:YES];

NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:
                 [CGTKCallbackData withObject:[CGTK class] 
                     andSEL:@selector(mainQuit)], @"endMainLoop",
                 [CGTKCallbackData withObject:[HelloWorld class] 
                     andSEL:@selector(hello)], @"on_button2_clicked",
                 [CGTKCallbackData withObject:[HelloWorld class] 
                     andSEL:@selector(hello)], @"on_button1_activate",
                 nil];

[builder connectSignalsToObjects:dic];

CGTKWidget *w = [builder getWidgetWithName:@"window1"];
if(w != nil)
{
    [w showAll];
}

[builder release];

So there you have it that’s CoreGTK in a nutshell.

There are a variety of ways to help me out with this project if you are so inclined to do so. The first task is probably just to get familiar with it. Download CoreGTK from the GitHub project page and play around with it. If you find a bug (very likely) please create an issue for it.

Another easy way to get familiar with CoreGTK is to help write/fix documentation – a lot of which is written in the source code itself. Sadly most of the current documentation simply states which underlying GTK+ function is called and so it could be cleaned up quite a bit.

At the moment there really isn’t anything more formal than that in place but of course code contributions would also be welcome!

Update: added some pictures of the same program running on all three operating systems.

Hello World on Windows

Hello World on Windows

Hello World on Mac

Hello World on Mac

Hello World on Linux

Hello World on Linux

This post originally appeared on my personal website here.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

Screen brightness work around (part 2)

January 19th, 2014 No comments

As mentioned before I am having some issues with my laptop’s hardware and controlling the screen brightness. Previously my work around was to set acpi_backlight=vender in the grub command line options. While this resulted in having full screen brightness it also removed my ability to use my keyboard function keys to adjust the screen brightness on the fly (not so good when you’re on battery). Removing this option allowed me to manually adjusted my screen brightness again but once again always started the laptop at zero brightness. What to do?

While far from a perfect solution my current work around is to use xdotool to simulate key presses on login which raise the screen brightness for me automatically. Here is the script that I run on startup:

#!/bin/bash
for i in {1..20}
do
     xdotool key XF86MonBrightnessUp
done

While this works great it still isn’t perfect. Because xdotool requires an X session it means I cannot run it before one is created. If you were unaware the login screen, in my case MDM, does not run inside of X (it actually starts X when you successfully login). So while this will automatically brighten my screen it won’t do so until I type in my username and password, leaving me to type into a fully dark screen or manually adjust the brightness up enough to see what I’m doing. Hopefully I’ll have a better solution sooner rather than later…




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

Listener Feedback Podcast Update (December 2013)

December 15th, 2013 No comments

Quite a few new Listener Feedback podcast episodes have been released in case you missed them:

There is also now a dedicated Ogg Vorbis podcast feed (containing all released episodes) for those of you who prefer that.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

Fix annoying high-pitched sound

November 28th, 2013 No comments

If you’re like me you’ve been suffering through a crazy high-pitched sound emanating from your laptop speakers. Apparently this is a common issue with certain types of audio devices. Thankfully via the power of the Internet I’ve been able to finally find a solution!

It turns out that the issue actually stems from some power saving features (of all things) in the Intel HDA driver. So I simply turned it off and guess what? It worked.

1) Open up (using root) /usr/lib/pm-utils/power.d/intel-audio-powersave

2) Replace or comment out the line:

INTEL_AUDIO_POWERSAVE=${INTEL_AUDIO_POWERSAVE:-true}

3) In its place put the line:

INTEL_AUDIO_POWERSAVE=false

4) Reboot

Hopefully this also works for you but if not check out the site I found the solution at for some additional tips/things to try.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

Fix no screen brightness on boot problem

October 14th, 2013 No comments

I recently upgraded my laptop to a brand new Lenovo Y410P and promptly replaced Windows 8 with a Linux install. Unfortunately I immediately ran into a very strange driver(?) issue where, on boot, the computer would default to the absolute lowest screen brightness level. This meant that I would need to manually adjust the screen brightness up just to see the login screen. Thankfully after some help from the excellent people over on the Ubuntu Forums I managed to find a very easy work around.

1) As root open up /etc/default/grub

I did this by simply issuing the following command:

sudo nano /etc/default/grub

2) Find the line that says GRUB_CMDLINE_LINUX= and add “acpi_backlight=vendor” to the list of options.

3) From a terminal run this command to update GRUB

sudo update-grub

4) Reboot!

That’s pretty much it. My computer now boots with the correct screen brightness as one would expect.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

Open source project hosting options

September 8th, 2013 2 comments

So you want to host an open source project using one of the many free services available but can’t decide which one to use? If only someone would put together a quick summary of each of the major offerings…

Hosting providers covered in this post:

  • Bitbucket
  • CodePlex
  • GitHub
  • Gitorious
  • Google Code
  • Launchpad
  • SourceForge

Bitbucket

Bitbucket is a hosting site for the distributed version control systems (DVCS) Git and Mercurial. The service offering includes an issue tracker and wiki, as well as integration with a number of popular services such as Basecamp, Flowdock, and Twitter.

Features:

  • Supports both Git and Mercurial
  • Allows private repositories for free, up to 5 users
  • Unlimited repositories
  • Has JIRA integration for issue tracking
  • Has its own REST API

Downsides:

  • Only allows up to 5 users for free (a user defined as someone with read or write access)

CodePlex

CodePlex is Microsoft’s free open source project hosting site. You can create projects to share with the world, collaborate with others on their projects, and download open source software.

Features:

  • Supports both Git & Mercurial
  • Integrated Wiki that allows to add rich documentation and nice looking pages
  • Bug Tracker and Discussion Forums included

Downsides:

  • Often times feels more like a code publishing platform than a collaboration site
  • Primarily geared toward .NET projects

GitHub

Build software better, together. Powerful collaboration, code review, and code management for open source and private projects.

Features:

  • Supports Git
  • Powerful and easy to use graphical tools
  • Easy team management
  • Integrated wiki, issue tracker and code review

Downsides:

  • Only supports Git
  • Quite a few ‘dead’ projects on the site

Gitorious

The Git hosting software that you can install yourself. Gitorious.org provides free hosting for open source projects that use Git.

Features:

  • Supports Git
  • Free project hosting
  • Integrated wiki
  • Can download the software and install it on your own server

Downsides:

  • Only supports Git

Google Code

Project Hosting on Google Code provides a free collaborative development environment for open source projects.

Features:

  • Supports Subversion, Mercurial Git
  • Integrated wiki

Downsides:

  • Not very pretty

Launchpad

Launchpad is a software collaboration platform.

Features:

  • Supports Bazaar
  • Integrated bug tracking and code reviews
  • Ubuntu package building and hosting
  • Mailing lists

Downsides:

  • Only supports Bazaar
  • Geared toward Ubuntu (which can be a downside depending on your project)

SourceForge

Find, Create, and Publish Open Source software for free.

Features:

  • Supports Git, Mercurial, Subversion
  • Integrated issue tracking, wiki, discussion forums
  • Stat tracking

Downsides:

  • Ads
  • A lot of ‘dead’ projects

 

Now obviously I’ve missed some things and glossed over others but my goal here was to provide a quick ‘at a glance’ summary of each. Check the individual websites for more. Thanks to the people over at Stack Exchange for doing a lot of the legwork.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

One license to rule them all? Noooooooooope!

August 20th, 2013 No comments

Lately I’ve been taking a look at the various open source software licenses in an attempt to better understand the differences between them. Here is my five minute summary of the most popular licenses:

GNU Public License (GPL)

Requires that any project using a GPL-licensed component must also be made available under the GPL. Basically once you go GPL you can’t go back.

Lesser GNU Public License (LGPL)

Basically the same as the GPL except that if something uses software licensed as LGPL it also doesn’t need to be licensed the same. So if you write a program that uses an LGPL library, say a program with a GTK+ user interface, it doesn’t need to be licensed LGPL. This is useful for commercial applications that rely on open source technology.

v2 vs v3

There are a number of differences between version 2 and version 3 of the GPL and LGPL licenses. Version 3 attempts to clarify a number of issues in version 2 including how patents, DRM, etc. are handled but a number of developers don’t seem to like the differences so version 2 is still quite popular.

MIT

This license allows for almost anything as long as a copy of the license and copyright are included in any distribution of the code. It can be used in commercial software without issue.

BSD3

Similar to the MIT, this license basically only requires that a copy of the license and copyright are included in any distribution of the code. The major difference between this and the MIT is that the BSD3 prohibits the use of the copyright holder’s name in any promotion of derivative work.

Apache

Apache is similar to the BSD license in that you have to provide a copy of the license in any derivative works. In addition there are a number of extra safeguards, such as patent grants, that set it apart from BSD.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.

The real lesson to take from Elementary OS

August 18th, 2013 No comments

Elementary OS is the latest darling for the Linux community at large and with some good reason. It isn’t that Elementary OS is The. Best. Distro. Ever. In fact being only version 0.2 I doubt its own authors would try to make that claim. It does however bring something poorly needed to the Linux desktop – application focus.

Focus?

Most distributions are put together in such a way as to make sure it works well enough for everyone that will end up using it. This is an admirable goal but one that often ends up falling short of greatness. Elementary OS seems to take a different approach, one that focuses on selecting applications that do the basics extremely well even if they don’t support all of those extra features. Take the aptly named (Maya) Calendar application. You know what it does? That’s right, calendar things.

Yeah, a calendar. What else were you expecting?

Yeah, a calendar. What else were you expecting?

Or the Geary e-mail client, another example of a beautiful application that just does the basics. So what if it doesn’t have all of the plugins that an application like Thunderbird does? It still lets you read and send e-mail in style.

It does e-mail

It does e-mail

Probably the best example of how far this refinement goes is in the music application Noise. Noise looks a lot like your standard iTunes-ish media player but that familiarity betrays the simplicity that Noise brings. As you may have guessed by now, it simply plays music and plays it well.

The best thing about Noise is that it plays music well

The best thing about Noise is that it plays music well

But what about feature X?

OK I understand that this approach to application development isn’t for everyone. In fact it is something that larger players, such as Apple, get called out over all the time over. Personally though I think there is a fine balance between streamlined simplicity and refinement. The Linux desktop has come a long way in the past few years but one thing that is still missing from a large portion of it is that refined user experience that you do get with something like an Apple product, or the applications selected for inclusion in Elementary OS. Too often open source projects happily jump ahead with new feature development long before the existing feature set is refined. To be clear I don’t blame them, programming new exciting features is always more fun than fixing the old broken or cumbersome ones, although this is definitely one area where improvements could be made.

Perhaps other projects can (or will) take the approach that Elementary has and dedicate one release, every so often, to making these refinements reality. I’m thinking something like Ubuntu’s One Hundred Paper Cuts but on a smaller scale. In the meantime I will continue to enjoy the simplicity that Elementary OS is currently bringing my desktop Linux computing life.




I am currently running a variety of distributions, primarily Linux Mint 17.
Previously I was running KDE 4.3.3 on top of Fedora 11 (for the first experiment) and KDE 4.6.5 on top of Gentoo (for the second experiment).
Check out my profile for more information.
Categories: Linux, Tyler B Tags: , , ,