Practical challenges for interrupt-free computing

My previous blog on interrupt-free computing has been very well read. I've had a look at some practical implementation possibilities and can share some more details about how to go about it and potential problems.

No perfect solution

They say that a certain billionaire is so rich that he would not spend 5 seconds bending over to pick up a $100 banknote on the ground because he makes $500 in 5 seconds anyway. A man from Ethiopia may well run a marathon for the same $100. This little anecdote underlines the point that no two people have exactly the same priorities and it is hard to provide a one-size-fits-all solution. A good technical solution needs to let the user have some control over their own priorities as that will go a lot further in respecting their preferences, their objectives and their environment.

A practical example: some users may not want to be disturbed by a VoIP call while watching a movie with their PC. Other users may be quite happy to receive these interruptions. Some users may want to only allow this interruption from a subset of possible callers.

Building blocks

In the original blog on this subject I suggested that Thunderbird and it's popular plugin, Mozilla Lightning calendar would provide one useful framework for integrating events, alerts and to-do items of various grades of importance. I already use these applications myself, from the re-branded icedove and iceowl-extension packages on Debian. They are also available in Fedora and many other distributions.

Priority with Lightning

An initial look at Lightning reveals a Priority attribute for tasks. It can be set to the values High, Medium or Low. These don't map to the concepts of Urgency and Importance from the Eisenhower method discussed in the original blog.

Potential hacks: there are two ideas that come to mind, with no coding changes:

• One possibility is to set Due dates for any item that has the Urgent characteristic and no date for items without the characteristic. In this case, the Priority attribute can then be used to distinguish Important and non-Important tasks.
• The other possibility is to use the Categories feature to define four categories: Urgent-Important, non-Urgent-but-Important, Urgent-non-Important and neither-Urgent-Important.

A more elegant solution would be to develop an additional plugin that provides new attributes for the Urgency and Importance characteristics. For server-side storage of these attributes, it would be feasible to use extension properties as defined in RFC 2445, for example, X-urgency and X-importance

This approach would make it easier to view a large range of tasks across multiple domains with the most urgent and important tasks at the top.

Ideally, the Categories attribute of tasks can be used to distinguish tasks that relate to work (or project/client) from personal tasks (such as planning a holiday)

Challenges with Lightning

Some of the challenges that I've identified after reviewing this solution:

• the Categories in Lightning don't appear to be synchronized with the Tags used in Thunderbird for email.
• Furthermore, the Tags are not synchronized automatically with the list of server-side IMAP keywords and somebody having multiple Thunderbird profiles (e.g. on both a desktop and a laptop) needs to manually synchronize the lists of tags and categories between all their devices.
• Many people use mobile devices such as smartphones and tablets to access their email, calendar and tasks. The lightweight mail/calendar clients on these devices don't support the full range of features for classification of content. Furthermore, their low-resolution user interfaces may even make it difficult to replicate the same experience on a mobile device. There is some hope, for example, rooting a tablet device and installing Linux would allow it to run a proper installation of Thunderbird with the various plugins described above.

Feeding system events and other data into the pipeline

Given the text-based nature of the iCalendar format, it should be easy enough for any application that is capable of generating mail to generate these iCal events with X-Urgency and X-importance properties. These events - such as alerts about security updates - could then be dispatched through the system's mailer. Some additional effort may be needed to avoid duplication.

The notification system in the desktop UI may then prioritize events from the mailbox rather than showing all alerts in real-time. Only applications that implicitly need to do so (such as VoIP/chat clients) would display notifications to the user directly.

Conclusion: Interrupting the user

Finally, after gathering all the events for the user in a mailbox like this, it would be possible for the plugin to be configured to interrupt the user only when some event reaches the user's own urgency/importance threshold. For example:

• The user may want to be interrupted for Urgent items with a deadline in less than 24 hours, but if the task has a `work' category, only interrupt during business hours
• For all other items, the user only sees them when they open Lightning or some other calendar/task management application to explicitly review things that they need to do.