chengliang zhang - Academia.edu (original) (raw)
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Papers by chengliang zhang
16th International Conference on Parallel Architecture and Compilation Techniques (PACT 2007), 2007
The use of multi-core, multi-processor machines is opening new opportunities for software specula... more The use of multi-core, multi-processor machines is opening new opportunities for software speculation, where program code is speculatively executed to improve performance at the additional cost of monitoring and error recovery. In this paper we describe a new system that use software speculation to support unsafely optimized code. We open a fast, unsafe track of execution but run the correct code on other processors to ensure correctness. We have developed an analytical model to measure the effect of major parameters including the speed of the fast track, its success rate, and its overheads. We have implemented a prototype and verified the correctness and performance using a synthetic benchmark on a 4-CPU machine.
In POPL 2002, Petrank and Rawitz showed a universal result—finding optimal data placement is not ... more In POPL 2002, Petrank and Rawitz showed a universal result—finding optimal data placement is not only NP-hard but also impossible to approximate within a constant factor if P= NP. Here we study a recently published concept called reference affinity, which characterizes a group of data that are always accessed together in computation. On the theoretical side, we give the complexity for finding reference affinity in program traces, using a novel reduction that converts the notion of distance into satisfiability. We also prove that ...
16th International Conference on Parallel Architecture and Compilation Techniques (PACT 2007), 2007
The use of multi-core, multi-processor machines is opening new opportunities for software specula... more The use of multi-core, multi-processor machines is opening new opportunities for software speculation, where program code is speculatively executed to improve performance at the additional cost of monitoring and error recovery. In this paper we describe a new system that use software speculation to support unsafely optimized code. We open a fast, unsafe track of execution but run the correct code on other processors to ensure correctness. We have developed an analytical model to measure the effect of major parameters including the speed of the fast track, its success rate, and its overheads. We have implemented a prototype and verified the correctness and performance using a synthetic benchmark on a 4-CPU machine.
In POPL 2002, Petrank and Rawitz showed a universal result—finding optimal data placement is not ... more In POPL 2002, Petrank and Rawitz showed a universal result—finding optimal data placement is not only NP-hard but also impossible to approximate within a constant factor if P= NP. Here we study a recently published concept called reference affinity, which characterizes a group of data that are always accessed together in computation. On the theoretical side, we give the complexity for finding reference affinity in program traces, using a novel reduction that converts the notion of distance into satisfiability. We also prove that ...