The Experts below are selected from a list of 240 Experts worldwide ranked by ideXlab platform

Matthew T. O'keefe - One of the best experts on this subject based on the ideXlab platform.

  • PLDI - Spill code minimization via Interference Region spilling
    Proceedings of the ACM SIGPLAN 1997 conference on Programming language design and implementation - PLDI '97, 1997
    Co-Authors: Peter Bergner, Peter Dahl, David Robert Engebretsen, Matthew T. O'keefe
    Abstract:

    Many optimizing compilers perform global register allocation using a Chaitin-style graph coloring algorithm. Live ranges that cannot be allocated to registers are spilled to memory. The amount of code required to spill the live range depends on the spilling heuristic used. Chaitin's spilling heuristic offers some guidance in reducing the amount of spill code produced. However, this heuristic does not allow the partial spilling of live ranges and the reduction in spill code is limited to a local level. In this paper, we present a global technique called Interference Region spilling that improves the spilling granularity of any local spilling heuristic. Our technique works above the local spilling heuristic, limiting the normal insertion of spill code to a portion of each spilled live range. By partially spilling live ranges, we can achieve large reductions in dynamically executed spill code; up to 75% in some cases and an average of 33.6% across the benchmarks tested.

Rui Dinis - One of the best experts on this subject based on the ideXlab platform.

  • Interference Characterization in Random Waypoint Mobile Networks
    IEEE Transactions on Wireless Communications, 2018
    Co-Authors: Luis Irio, Rodolfo Oliveira, Luis Bernardo, Antonio Furtado, Rui Dinis
    Abstract:

    In this paper, we characterize the wireless Interference of a mobile ad hoc network, where the nodes move according to the random waypoint model. The interferers are assumed to be located within an Interference Region that is defined as a circular Region centered in a fixed node located at a given point of the mobility scenario. The main contribution of this paper is the characterization of the aggregate Interference caused to the fixed node by mobile interferers located within the Interference Region. The distribution of the Interference is analyzed taking into account the stochastic nature of the path loss due to the mobility of the nodes, as well as fast fading and shadowing effects. The derivation of the characteristic function of the aggregate Interference is used in two different estimators, which successfully characterize the Interference using only a small set of samples. The theoretical approach is validated through simulations, which confirm its effectiveness. Finally, we assess the accuracy of the proposed estimators, demonstrating the practical value of this paper.

Peter Bergner - One of the best experts on this subject based on the ideXlab platform.

  • PLDI - Spill code minimization via Interference Region spilling
    Proceedings of the ACM SIGPLAN 1997 conference on Programming language design and implementation - PLDI '97, 1997
    Co-Authors: Peter Bergner, Peter Dahl, David Robert Engebretsen, Matthew T. O'keefe
    Abstract:

    Many optimizing compilers perform global register allocation using a Chaitin-style graph coloring algorithm. Live ranges that cannot be allocated to registers are spilled to memory. The amount of code required to spill the live range depends on the spilling heuristic used. Chaitin's spilling heuristic offers some guidance in reducing the amount of spill code produced. However, this heuristic does not allow the partial spilling of live ranges and the reduction in spill code is limited to a local level. In this paper, we present a global technique called Interference Region spilling that improves the spilling granularity of any local spilling heuristic. Our technique works above the local spilling heuristic, limiting the normal insertion of spill code to a portion of each spilled live range. By partially spilling live ranges, we can achieve large reductions in dynamically executed spill code; up to 75% in some cases and an average of 33.6% across the benchmarks tested.

Luis Irio - One of the best experts on this subject based on the ideXlab platform.

  • Interference Characterization in Random Waypoint Mobile Networks
    IEEE Transactions on Wireless Communications, 2018
    Co-Authors: Luis Irio, Rodolfo Oliveira, Luis Bernardo, Antonio Furtado, Rui Dinis
    Abstract:

    In this paper, we characterize the wireless Interference of a mobile ad hoc network, where the nodes move according to the random waypoint model. The interferers are assumed to be located within an Interference Region that is defined as a circular Region centered in a fixed node located at a given point of the mobility scenario. The main contribution of this paper is the characterization of the aggregate Interference caused to the fixed node by mobile interferers located within the Interference Region. The distribution of the Interference is analyzed taking into account the stochastic nature of the path loss due to the mobility of the nodes, as well as fast fading and shadowing effects. The derivation of the characteristic function of the aggregate Interference is used in two different estimators, which successfully characterize the Interference using only a small set of samples. The theoretical approach is validated through simulations, which confirm its effectiveness. Finally, we assess the accuracy of the proposed estimators, demonstrating the practical value of this paper.

  • Aggregate Interference in Random Waypoint Mobile Networks
    IEEE Communications Letters, 2015
    Co-Authors: Luis Irio, Rodolfo Oliveira, Luis Bernardo
    Abstract:

    In this work, we characterize the wireless Interference of a mobile ad hoc network, where the nodes move according to the Random Waypoint model. The interferers are assumed to be located within an Interference Region, which is defined as a circular Region centered in a fixed node located in the center of the mobility scenario. The main contribution of this letter is the characterization of the aggregate Interference caused to the fixed node by the mobile interferers located within the Interference Region. The distribution of the Interference is analyzed taking into account the stochastic nature of the path loss due to the mobility of the nodes. The theoretical approach is validated through simulations, which confirm its effectiveness.

Ray-guang Cheng - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic scheduling framework on an RLC/MAC layer for general packet radio service
    IEEE Transactions on Wireless Communications, 2003
    Co-Authors: Jen-shun Yang, Chien-chao Tseng, Ray-guang Cheng
    Abstract:

    We present a traffic-scheduling framework that can dynamically allocate radio resources to a general packet radio service (GPRS) mobile station (MS) based on the Interference levels of the radio links and the quality of service (QoS) specification of the MS. The underlying idea of this scheduling scheme is to preserve more bandwidth for use by those MSs that are within a low Interference Region so that the limited radio resources can be used more effectively. In this scheme, an MS uses a low transmission rate for data transfer when the MS is within a high Interference Region to avoid wasting bandwidth by transmitting data in a condition with high Interference. In order to compensate for the service loss of the MS, we allocate more bandwidth to the MS when it is within a low Interference Region. In addition, we also propose an analytical model that can be used to derive the transmission rate for an MS in a low Interference Region based on the delay-bound requirement of the MS. The performance results show that our dynamic scheme can utilize the bandwidth more effectively to satisfy various QoS requirements of the MSs in the GPRS system without changing the convolution-coding rate.

  • ICDCS Workshops - Dynamic scheduling framework on RLC/MAC layer for general packet radio service
    Proceedings 21st International Conference on Distributed Computing Systems Workshops, 1
    Co-Authors: Jen-shun Yang, Chien-chao Tseng, Ray-guang Cheng
    Abstract:

    We present a traffic-scheduling framework which can dynamically allocate radio resource to GPRS handsets based on the Interference levels of the radio links. Essentially, when a mobile station (MS) is within a high Interference Region, the proposed scheme uses a low transmission rate to reduce bandwidth wastage due to re-transmissions. On the other hand, when the MS is within a low Interference Region, a high transmission rate is used, in order to fulfil its quality of service (QoS) requirements. One of our contributions is to derive a rate decision analytical model to determine the high and low transmission rates based on the Interference conditions and the delay-bound requirement. The performance results show that our dynamic scheme can effectively utilize the bandwidth to satisfy various QoS requirements in the GPRS system without changing the convolution-coding rate.