The LogP machine is a model for parallel computation. It aims at being more practical than the PRAM model while still allowing for easy analysis of computation. The name is not related to the mathematical logarithmic function.
The LogP machine consists of arbitrarily many processing units with distributed memory. The processing units are connected through an abstract communication medium which allows point-to-point communication. This model is pair-wise synchronous and overall asynchronous.
Culler, David; Karp, Richard; Patterson, David; Sahay, Abhijit; Schauser, Klaus Erik; Santos, Eunice; Subramonian, Ramesh; Von Eicken, Thorsten (July 1993), “LogP: Towards a realistic model of parallel computation” (PDF), ACM SIGPLAN Notices, 28 (7): 1–12, CiteSeerX 10.1.1.319.7827, doi:10.1145/173284.155333