Archive for the ‘Linux’ Category

Currently getting 400ms ping times to my wi-fi access point, and about 16k/second to my file server over my ‘150Mbps’ wi-fi connection. Plug in an Ethernet cable, and the ping is down to 0.25ms.

Remind me never to buy another laptop with Realtek wi-fi.

How is it that I can install Linux from scratch faster than I can install Windows drivers for a new scanner?

Finally got around to upgrading. So far it works no worse than 16, except my fancy login screen has been replaced with some crappy username/password entry box, and encrypted swap partitions no longer work (apparently the latter is a known bug).

Here’s roughly how I did it:

1. Use the backup tool to save a list of installed applications.
2. Boot up, plug in the USB backup drive and log in to a console terminal.
3. cd /tmp and sudo -i to become root, not in my own home directory.
4. Since I have an encrypted home directory, I now want to unmount /home/emg so nothing can write to the directory while I’m backing it up. So umount /home/emg.
5. Copy /home to the backup drive. This saves an encrypted backup which can be reloaded if everything goes horribly wrong.
6. While doing that, make a list of the partitions on the disk.
7. Unmount the backup drive, unplug it, and reboot on the install disk.
8. Select to install. Select all partitions other than /home, and choose to reformat them and install.
9. Set the hostname and username, and ensure you pick the same password as you had before, so the encrypted home directory will work.
10. Install.
11. Reboot.
12. Edit /etc/fstab to mount the old home partition as /home.
13. Reboot.
14. Log in as yourself, update (in my case, I had to download about 400 upgraded packages) and finish installing the packages you need.
15. Reboot for safety. Job done.

Seems to be getting worse; now there’s flashing red crap on the screen, and I sometimes have to boot fifteen times to get a screen that isn’t all green.

Any time I boot into hardware-accelerated mode, whereas it displays fine when booting as a dumb framebuffer. Sadly, I tried the Mint 17 LiveCD, and, if anything, it’s even worse.

So, warning to the wise: if you’re buying a new laptop, don’t get one with Intel integrated graphics.

Arrived on my Nexus 7 today. I can’t see any obvious difference, but it was only supposed to be a bug-fix release. Download and install was pretty fast, so I doubt much changed.

So, I bought a new laptop and it’s just about working. It’s a Toshiba L70-A-04g, which was the best option I could find in a local store. Mostly because of the 17″ screen, because I wanted something that would fit more text than the old 15″, but also because it has a HDD cover underneath, while the 15″ models I looked at typically required removing sixteen screws and then pushing a credit card in around the edge to unlatch the entire base.

It kind of works. I removed the Windows 8 HDD and installed my Linux SSD from the old laptop, then configured the BIOS to legacy boot, and… ended up at a black screen. Mint 16 doesn’t understand the backlight, so I had to add acpi_backlight=vendor to the boot command.

Unfortunately it also doesn’t work properly with the HD4600 Intel video driver. In the past, buying a machine that’s all-Intel has been the safest option, but not here. There’s a lot of video corruption as the driver starts, and some flickering pixels at the top of the screen. I suspect it’s a video timing bug that’s been fixed in the 3.15 kernel, but that won’t hit Mint for several months. The other option is to run in VESA mode, but then you’re stuck with software rendering and the CPU running flat out for video playback.

The touchpad is abysmal, for some reason they’ve combined the mouse buttons into the touchpad, they take a heck of a force to click, and, if you click one while your finger is on the touchpad, you have to lift your finger and put it back down to get the touchpad to recognize it again. The old one was far better.

So, it appears Libreoffice is now crashing regularly for no obvious reason, with a segmentation fault in libmergedlo.so; it seems to be a known bug that’s been around for months with no fix. This is particularly annoying because I save the file, do something, it crashes, and, when I restart it, the file I load is not the one I saved.

Since it’s crashed three times in the last fifteen minutes, this makes writing pretty damn tiresome right now. I presume it’s somehow graphics driver related, because it didn’t happen on the old laptop, but happens regularly on this one. That said, it’s also happened on my desktop machine at work.

Someone suggested uninstalling Java, and, since I did that, it hasn’t crashed. Which is weird, because I had the Java integration disabled before then. It may just be a coincidence.

Pause and restore now actually works again in Linux Mint 16. Which is useful; I no longer have to exit and restart every time I need to stop the music for a moment.

Looks like the NFS and slow login issue is due to NFS now requiring GSSD. I seem to have solved it by setting ‘NEED_GSSD=yes’ in /etc/default/nfs-common on both client and server, and rebooting both.

The Cardo issue appears to be a problem with the font. I found a bug related to it on Red Hat:

Cardo font unusable, badly displayed

Using Fontforge to edit the OS/2 Metrics to the values specified there, and similar values for the bold font, appears to have solved the problem. The italic font appears to always have been OK.

Finally got around to upgrading from 15 as it’s now end of life. I tried the suggested method to upgrade without having to reinstall:

Upgrade Linux Mint 15 (Olivia) to Linux Mint 16 (Petra)

But that failed horribly. The system would boot, but the MDM couldn’t find its theme; I could log in from a console and start the X server myself, but half the MATE applets were missing. Any attempt to fix it by uninstalling MATE and reinstalling ran into a load of conflicts.

So, eventually, I gave in and just reinstalled from scratch.

Three things I’ve noticed so far:

1. Logging in takes about ten times as long as before.
2. Automounter takes about ten seconds to mount an NFS partition.
3. Cardo font is completely screwed up in LibreOffice 4.1. I suspect this is a known bug that’s fixed in 4.2, so I’m going to have to manually install that.

Nope, Cardo is hosed. I’ve had to fight through all the crap required to setup a bugzilla account, and report the bug:

Bugzilla

Rhythmbox has broken pause sometime in the last few months. Now, any time I pause and then try to start again, it just keeps jumping onto new songs without playing anything.

Anyone know what broke it, and how to fix that?

I was updating my Xbmc machine, which we use to play videos recorded by MythTV. Running apt-get kept complaining that it was out of disk space, yet ‘df’ showed there was plenty on every partition.

Turns out that’s because it’s lying. It’s not out of disk space, it’s out of inodes. For some reason it’s not cleaning up old kernels, and is leaving the kernel headers in /usr/src. That’s a staggering number of tiny files that eat up inodes much faster than they eat up disk space.

So, if you see this error, you need to remove old kernels and headers to clean up space.

Screenshot

Diff PDF comparing versions

Just discovered this program today, which is included in the Linux Mint repositories. It’s insanely useful for checking Createspace PDF files, as it shows all the differences between the new version and the old version; if you’re just changing a typo or a few poorly phrased words you can verify that everything else is the same as the previous version without requiring a full proofreading session.

Another issue I just ran into with Linux Mint 15 is the switch to version 1.7 of the Subversion source control system. It refuses to update existing 1.6 files, and you first have to do an ‘svn upgrade’ to upgrade them to 1.7.

But after you do that, any attempt to retrieve a file with an SVN external will result in a W195017 error complaining that the SVN external can’t overwrite a versioned file. Which is completely bogus.

Fetching external item into 'HTML/include/images/petrina-250.jpg':
svn: warning: W195017: The file external from 'svn://Stories/trunk/Covers/Petrina/petrina-250.jpg' cannot overwrite the existing versioned item at 'HTML/include/images/petrina-250.jpg'

Even deleting the old file doesn’t work. The svn update still complains even though the file isn’t there.

The only workaround I found is to convince svn that the file has been deleted by using ‘svn -r0 filename’ to revert it to revision 0. Then it will pull the SVN external on top of it.

$ svn up -r0 HTML/include/images/petrina-250.jpg
Updating 'include/images/petrina-250.jpg':
D include/images/petrina-250.jpg
Updated to revision 0.

But it’s a real pain for something that should just work out of the box.

Mint 15 is working pretty well so far aside from my previously mentioned issues with the wireless card in my laptop. Problems ranged from high dropped packet rates to disconnects to the truly bizarre, such as inability to ping the wireless access point it’s connected to yet being able to ping the other machines it’s connected to through that access point. Since that is also the default gateway, that means it loses any connectivity to the outside world.

After a web search, the solution appears to be disabling hardware encryption. The wireless chip is apparently overloaded trying to do the encryption as well as everything else it has to do, which makes sense because it would normally go horribly wrong when starting Firefox, which hits the Internet to download a number of web pages when restoring the old configuration.

To do this, create a file /etc/modprobe.d/rtl8192se.conf and put the following line in it:

options rtl8192se swenc=1

This forces software encryption, which appears to be an insignificant overhead on an i5 CPU. Since enabling this I’ve run for a few hours with no problems, but I’ll update this if I do.

My laptop is now running Linux Mint 15 on a new Intel 520 SSD. Boots in a few seconds and pretty much back to the old Gnome 2 interface with some enhancements.

So far it seems to work well other than some odd behaviour by my wireless card, and the process was relatively painless. I had to update a few OS configuration files, install missing packages, and then put the old hard drive in a USB box and copy /home over to the SSD.

But for some reason the 8192SE wireless card won’t run at more than 18Mbps even when it’s two feet from the wireless access point. I didn’t actually check what speed it was running at in Ubuntu 12.04, so this may have always been the case. It’s consistent with the throughput I’ve seen between the laptop and my home server (around 1-1.5 megabytes per second).

I’ve been testing out the Linux Mint 15 release candidate today and it looks pretty neat. Having Gnome back is definitely an improvement over the various annoyances I’ve had to live with in XFCE. Since I no longer use my laptop for Windows games I’m planning to replace the hard drive with an SSD shortly so Mint will probably replace Ubuntu at the same time unless I run into any show-stopper issues.

Of course if Ubuntu would officially support MATE (the Gnome 2 fork) I wouldn’t have to…

If you’re running Linux and wondering where all your disk space has gone, check the Wine temporary directories under C:/windows. I was almost out of space, and deleting all the junky temporary files freed up eight gigabytes.