標題: | Reschedulable-Group-SCAN scheme for mixed real-time/non-real-time disk scheduling in a multimedia system |
作者: | Chang, HP Chang, RI Shih, WK Chang, RC 資訊工程學系 Department of Computer Science |
關鍵字: | real-time disk scheduling;mixed workload;multimedia database/file systems;operating system |
公開日期: | 15-十一月-2001 |
摘要: | Real-time disk scheduling is important for time-critical multimedia applications. Previous approaches, such as SCAN-earliest deadline first (EDF) or DM-SCAN, applied the SCAN scheme to reschedule service sequence of input tasks to reduce tasks' service time. However, they required the input to be in EDF order. In DM-SCAN, a deadline modification scheme was employed to obtain a pseudo-EDF sequence from non-EDF ordered input tasks. Because the modified deadlines were smaller than the original ones, number of tasks that could be rescheduled is decreased and thus data throughput is reduced. In this paper, we propose Reschedulable-Group-SCAN (RG-SCAN), a new real-time disk scheduling algorithm using the concept of Reschedulable-Group (R-Group). Differing from previous approaches, RG-SCAN has no limitation on the input task's sequence. In addition, by exploiting the service time's reduction after rescheduling in each R-Group, RG-SCAN has been extended to serve mixed real-time and non-real-time workloads. As shown in experimental results. our approach can support more tasks than DM-SCAN, both real-time and non-real-time. Additionally, our approach can provide larger data throughput and offer better response time to non-real-time tasks. For example, given 30 random-generated real-time tasks, the number of non-real-time tasks that can be supported by RG-SCAN is 1.3 times that supported by DM-SCAN. In addition, our data throughput is 1.1 times DM-SCAN's. (C) 2001 Elsevier Science Inc. All rights reserved. |
URI: | http://dx.doi.org/10.1016/S0164-1212(01)00058-9 http://hdl.handle.net/11536/29248 |
ISSN: | 0164-1212 |
DOI: | 10.1016/S0164-1212(01)00058-9 |
期刊: | JOURNAL OF SYSTEMS AND SOFTWARE |
Volume: | 59 |
Issue: | 2 |
起始頁: | 143 |
結束頁: | 152 |
顯示於類別: | 期刊論文 |