1 Department of Applied Mathematics and Computer Science, Technical University of Denmark2 Embedded Systems Engineering, Department of Applied Mathematics and Computer Science, Technical University of Denmark3 Purdue University4 Purdue University
Transactional memory is a promising technique for enforcing disciplined access to shared data in a multiprocessor system. Transactional memory simplifies the implementation of a variety of concurrent data structures. In this paper, we study the benefits of a modest, real-time aware, hardware implementation of transactional memory that we call micro-transactions. In particular, we argue that hardware support for micro-transactions allows us to efficiently implement certain data structures. Those data structures are difficult to realize with the atomic operations provided by stock hardware and provide real-time guarantees for those operations. Our main implementation platform is the Java Optimized Processor system, a field-programmable gate array (FPGA) implementation of the Java virtual machine, optimized for real-time Java. We report on the performance of data structures implemented with locks, atomic instructions, and micro-transactions. Our results suggest that transactional memory is an interesting alternative to traditional concurrency control mechanisms.
Concurrency and Computation: Practice and Experience, 2013, Vol 25, Issue 16