Abstract: Resource reservation is an important way for supporting quality of service in grid computing.However，advance reservations can lead to a reduced performance of grid applications，because resource fragments are resulted in while reserving.A new reservation mechanism is proposed in this paper，which is called as Task Dividable based Reservation（TDR）.In presented mechanism，resource reservations are very flexible and can transform in all directions，and within limitation of request，a reservation may be divided into small reservations that are defined as sub-reservations，so as to the performance of the network may be increased.The corresponding algorithm of admission control for TDR is presented.Performance studies based on simulations are carried out also，and the results show that the proposed mechanism outperforms existed similar mechanisms in the important performance metrics：call acceptance rate and bandwidth usage.

Key words: grid, resource reservation, task dividable, QoS

摘要： 资源预留能提供保证QoS的网格服务，但提前预留会增加服务请求拒绝率，且产生的资源碎片降低了资源利用率。在预留分类和预留容量等概念定义的基础上，提出了一种基于可分割任务的网格资源预留机制TDR。TDR中，资源预留在多个方向具有可变的灵活度，并在一定的条件下被分割为多个子预留，从而提高系统容纳能力，并描述了相应的接纳控制算法。仿真实验结果表明，提出的机制能有效地减少预留产生的资源碎片和请求拒绝率，增加资源利用率。

关键词: 网格, 资源预留, 任务可分, 服务质量