2 years, 8 months ago.

Fail safe File system in the new OS?

I am using Mbed OS for a few embedded apps. And the greatest advantage of Mbed OS is that even if I do a power reset when app is running, the app starts flawlessly.

In Linux like OS (for example Raspbian on Raspberry Pi), file system is not fail safe when for example power interruption. Desktop Linux such as Ubuntu or Raspbian, may use UPS (Uninterrupted Power Supply) to avoid OS crash due to power failure. However such solutions are not always feasible in case of Embedded systems.

With the announcement of this new OS for Cortex-A MCU, I am delighted because now embedded App can enjoy advantages of Linux like OS. However I have following question:

Will the new OS posses same robustness, simplicity of Mbed OS along with power of Linux?

Question relating to:

Even with Ubuntu in Raspberry Pi You can make it reasonably robust. To the point what you can hit the "reset" button at any time. The trick is to boot from a read-only file system. You can do all your writes to either a RAM based file system or to a different device or different partition. In Linux typically /var and /tmp need to be writable but everything else can be read-only.

In the very-old days we used to cut a conductor on a ribbon cable to prevent any chance of writing to a drive. You would have to physically swap the cable back to make a change. But today just edit the /etc/fstab. to include "ro" (read-only) in the options

posted by Chris Albertson 19 Oct 2018

Yes I have done these solutions in a few projects. However I wanted a built-in solution as already informed by Naveen.

posted by Hemant Joshi 29 Nov 2018

1 Answer

2 years, 7 months ago.

Hi Hemant, All the critical functions in Mbed Linux OS, like update and boot, will be resilient to power failure, and Mbed Linux OS uses an ext4 flash filesystem that is tolerant to power failures. We welcome your feedback if you have specific concerns or proposals.



Team mbed.

Thanks Naveen for the confirmation. What is the schedule for the releases?

posted by Hemant Joshi 29 Nov 2018