Cello: A Disk Scheduling Framework for Bext Generation Operating Systems

In this paper, we present the Cello disk scheduling framework for meeting the diverse service requirements of applications. Cello employs a two-level disk scheduling architecture, consisting of a class-independent scheduler and a set of class-specific schedulers. The two levels of the framework allocate disk bandwidth at two time-scales: the class-independent scheduler governs the coarse-grain allocation of bandwidth to application classes, while the class-specific schedulers control the fine-grain interleaving of requests. The two levels of the architecture separate application-independent mechanisms from application-specific scheduling policies, and thereby facilitate the co-existence of multiple class-specific schedulers. We demonstrate that Cello is suitable for next generation operating systems since: (i) it aligns the service provided with the application requirements, (ii) it protects application classes from one another, (iii) it is work-conserving and can adapt to changes in work-load, (iv) it minimizes the seek time and rotational latency overhead incurred during access, and (v) it is computationally efficient.

[1]  Randy H. Katz,et al.  An analytic performance model of disk arrays , 1993, SIGMETRICS '93.

[2]  Prashant J. Shenoy,et al.  Symphony: an integrated multimedia file system , 1997, Electronic Imaging.

[3]  Chung Laung Liu,et al.  Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment , 1989, JACM.

[4]  Miron Livny,et al.  Priority in DBMS Resource Scheduling , 1989, VLDB.

[5]  Yale N. Patt,et al.  Scheduling algorithms for modern disk drives , 1994, SIGMETRICS 1994.

[6]  Margo I. Seltzer,et al.  Disk Scheduling Revisited , 1990 .

[7]  Micha Hofri.  Disk scheduling: FCFS vs.SSTF revisited , 1980, CACM.

[8]  Jason Nieh,et al.  The design, implementation and evaluation of SMART: a scheduler for multimedia applications , 1997, SOSP.

[9]  Robert Geist,et al.  A continuum of disk scheduling algorithms , 1987, TOCS.

[10]  A. L. Narasimha Reddy,et al.  Disk scheduling in a multimedia I/O system , 1993, MM 1993.

[11]  John P. Lehoczky,et al.  An optimal algorithm for scheduling soft-aperiodic tasks in fixed-priority preemptive systems , 1992, [1992] Proceedings Real-Time Systems Symposium.

[12]  Micha Hofri,et al.  On the Expected Performance of Scanning Disks , 1982, SIAM J. Comput..

[13]  Banu Özden,et al.  Disk scheduling with quality of service guarantees , 1999, Proceedings IEEE International Conference on Multimedia Computing and Systems.

[14]  Paul Barham,et al.  A fresh approach to file system quality of service , 1997, Proceedings of 7th International Workshop on Network and Operating System Support for Digital Audio and Video (NOSSDAV '97).

[15]  Harrick M. Vin,et al.  Start-time fair queueing: a scheduling algorithm for integrated services packet switching networks , 1996, SIGCOMM 1996.

[16]  Michael B. Jones,et al.  Support for User-Centric Modular Real-Time Resource Management in the Rialto Operating System , 1995, NOSSDAV.

[17]  H. Garcia-Molina,et al.  Scheduling I/O requests with deadlines: A performance evaluation , 1990, [1990] Proceedings 11th Real-Time Systems Symposium.

[18]  Guru M. Parulkar,et al.  Enhancements to 4.4 BSD UNIX for efficient networked multimedia in project MARS , 1998, Proceedings. IEEE International Conference on Multimedia Computing and Systems (Cat. No.98TB100241).

[19]  Neil C. Wilhelm.  An anomaly in disk scheduling: a comparison of FCFS and SSTF seek scheduling using an empirical model for disk accesses , 1976, CACM.

[20]  Ramesh Govindan,et al.  A file system for continuous media , 1992, TOCS.

[21]  Peter J. Denning,et al.  Effects of scheduling on file memory operations , 1899, AFIPS '67 (Spring).

[22]  Ragunathan Rajkumar,et al.  Real-time filesystems. Guaranteeing timing constraints for disk accesses in RT-Mach , 1997, Proceedings Real-Time Systems Symposium.

[23]  Edward G. Coffman,et al.  Analysis of Scanning Policies for Reducing Disk Seek Times , 1972, SIAM J. Comput..

[24]  Ravi Wijayaratne,et al.  Providing QOS guarantees for disk I/O , 2000, Multimedia Systems.

[25]  Toby J. Teorey,et al.  A comparative analysis of disk scheduling policies , 1972, CACM.