The Slothful Ways of D-Bus

It's a common belief that D-Bus is “slow”, but there's relatively little quantitative data on what exactly is slow about it, how slow it actually is, and—perhaps most importantly—why. This talk will discuss a detailed study—conducted primarily by Alban Crequy and Robin Bate Boerop—into the throughput and latency characteristics of the reference implementation of D-Bus, and the variables affecting these characteristics, such as message size, connected clients, and other factors. Armed with these concrete facts, Will will talk about the areas it might be most beneficial to focus on, and possible approaches to solving the issues discovered.

Of course, not every D-Bus issue can be blamed on the transport implementations: many applications fall into pessimal usage patterns, often without realising. So this talk will also discuss the methods that can be used to find and examine inefficient use of D-Bus, such as statistics retrieved from the bus daemon itself. Inevitably, Will will wax lyrical about Bustle, a pointy-clicky D-Bus activity viewer, which is growing statistics built into the UI, as well as searching, filtering, and monitoring activity in real time.