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Clocks function as media objects in at least two ways. First, they create shared senses of temporality. Second, they facilitate technologically mediated auditory communication. When clocks fall out of sync with one another, the result is a type of noise that signal- processing engineers call jitter. Jitter is, in turn, managed through practices known as clocking. Drawing on technical engineering literature and an ethnography of Los Angeles- based recording professionals, I articulate a broader sociotechnical definition of jitter and clocking, which I use to analyze three sites of temporal negotiation in the recording process: (1) the organization of clock signals in the analog-to-digital conversion process; (2) the production of the studio as a heterochrony or “other time,” distinct from the world outside the studio; and (3) the reconciliation of human and nonhuman temporalities, exemplified in the interaction between a drummer and a drum machine. I further consider jitter’s conceptual affordances for media studies generally.
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Power Clocks: Dynamic Multi-Clock Management for Embedded Systems
This paper presents Power Clocks, a kernel-based dy- namic clock management system that reduces active en- ergy use in embedded microcontrollers by changing the clock based on ongoing computation and I/O requests. In Power Clocks, kernel hardware drivers asynchronously re- quest clocks, providing a set of constraints (e.g., maximum speed), which the kernel uses to dynamically choose the most efficient clock. To select a clock, Power Clocks makes use of the observation that though slower clocks use less power and are suited for fixed time I/O operations, faster clocks use less energy per clock tick, making them opti- mal for pure computation. Using Power Clocks, a networked sensing application consumes 27% less energy than the best static clock, and within 3% of an optimal hand-tuned dy- namic clock strategy. Power Clocks provides similar energy savings even when there are multiple applications.
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- Award ID(s):
- 1931750
- PAR ID:
- 10292320
- Date Published:
- Journal Name:
- 6th Annual International Conference on Distributed Computing in Sensor Systems (DCOSS 2020)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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