We have reached the 2015-Q4 milestone (and just barely in time). There are significant changes in this release, so even if you are an experienced ev3dev user, read on…

Reporting Issues

Since there are so many changes with this release, we expect there to be new issues. If you have trouble, check out the support page and let us know about it. Just a friendly reminder… Please don’t comment on a closed issue (unless you are asking to re-open the issue or confirming that it is indeed fixed). It’s always best to open a new issue. It also keeps @dlech happy and sane.

Default User

We are no longer using root:r00tme as the default user:password. The new default user name is robot and the password is maker. Only files in /home/robot/ will show up in the File Browser in the Brickman user interface.

File Permission Issues

We discovered that the method we were previously using to create image files was fundamentally flawed with regard to file permissions. Basically, every file on the image was owned by root:root even if it was supposed to be owned by someone else. This caused problems with programs that relied on these file permissions.

This issue has been fixed, but unfortunately that means that if you are already using ev3dev, you need to re-flash your SD card in order to fix these issues. Don’t forget to backup any important files before you re-flash!

Raspberry Pi

This is the first release that supports mindsensors.com PiStorms out of the box. Note: You will need a USB keyboard or (10-digit keypad with backspace) in order to use the Brickman user interface.

We’ve also added a driver for battery indication on BrickPi+.

Open-Roberta Lab

Thanks to the work of @ensonic, we now have support for https://lab.open-roberta.org out-of-the-box. It is prevented from running by default, so you do have to start it manually…

sudo systemctl unmask openrobertalab.service
sudo systemctl start openrobertalab.service

After running the commands above, it will start automatically after a reboot. You can turn it back off by running…

sudo systemctl stop openrobertalab.service
sudo systemctl mask openrobertalab.service

Bigger Font

One of the most noticeable changes is that we are using a bigger font in the Brickman user interface. This font looks big on the EV3 but is actually kind of small on the PiStorms.

Changing the font size broke lots of screens in Brickman. We have fixed most of them, but if you find something that doesn’t look right, let us know.

Faster Swap

Linux uses what is called a swapfile for virtual memory. This means when your computer (or EV3) starts to run out of RAM, it moves some of the information to the swapfile to free up some RAM.

Conventionally, the swapfile is a file or partition on your hard drive. Hard drives are much slower than RAM, so when you are using too much memory your computer starts running really slow because it is moving memory back and forth between the fast RAM and the slow hard drive.

With ev3dev, we are running on an SD card, which is even way slower than a hard drive. The EV3 also only has 64MB of RAM, so it can run out of RAM rather quickly. In the past, we have had the swapfile on the SD card in various forms, but this is not so good for two reasons. 1) It makes the EV3 super slow when memory is swapped and 2) it will wear out your SD card faster because of writing to it all of the time.

So, what can we do to make this better? In this release, we are using zram instead. Zram is a relatively new Linux kernel feature that stores information compressed in RAM. We use this to create a compressed RAM disk for the swapfile. This way when the memory starts getting full, it is compressed to free up space.

The processor has to do extra work to compress the information, so it still makes the EV3 run slower, but it is actually still faster than writing to the SD card. So, hopefully this release should run a little faster and your SD card will last a little longer.

Note: ZRAM is currently only enabled on the EV3. The Raspberry Pi images do not have any swapfile enabled since they have plenty of RAM.


So, you want to download this release? Of course you do! Click here.

Post Info

  • Posted on 30 December 2015