Even better than putting developers from all those projects in the same room, in the morning there were a couple presentations from tracing users: Frank Rowand and Vinod Kutty who use tracing on embedded systems and financial trading servers, respectively. The danger of inward-facing development conferences is that design decisions can be made based on what developers think the end-users want… but talking to those end-users directly is essential. Kudos to the organizers, Dominique Toupin and Mathieu Desnoyers, for arranging for those talks.
So what did they have to say?
- the term “embedded” spans the range from low-end cameras to wall-sized video editing consoles (this isn’t news to anybody doing embedded development)
- embedded devices are often very storage-constrained, so they can’t hold a lot of trace data, and CPU-constrained, so the tracing needs to be low-overhead
- desirable things to trace in embedded systems include power consumption, memory usage, and boot time
- high-frequency trading is about minimizing latency (on the order of microseconds), to the point that they disable power-saving because CPU speed transitions take too long
- recent technologies like RDMA, OpenOnload, and DPAA are bypassing the kernel, so tracing solutions must cover userspace too