This Article 
 Bibliographic References 
 Add to: 
Systems Support for Preemptive Disk Scheduling
October 2005 (vol. 54 no. 10)
pp. 1314-1326
Allowing higher-priority requests to preempt ongoing disk IOs is of particular benefit to delay-sensitive and real-time systems. In this paper, we present Semi-preemptible IO, which divides disk IO requests into small temporal units of disk commands to improve the preemptibility of disk access. We first lay out main design strategies to allow preemption of each component of a disk access—seek, rotation, and data transfer, namely, seek-splitting, JIT-seek, and chunking. We then present the preemption mechanisms for single and multidisk systems—JIT-preemption and JIT-migration. The evaluation of our prototype system showed that Semi-preemptible IO substantially improved the preemptibility of disk access with little loss in disk throughput and that preemptive disk scheduling could improve the response time for high-priority interactive requests.

[1] K. Jeffay, D.F. Stanat, and C.U. Martel, “On Non-Preemptive Scheduling of Periodic and Sporadic Tasks,” Proc. 12th IEEE Real-Time Systems Symp., Dec. 1991.
[2] D.I. Katcher, H. Arakawa, and J.K. Strosnider, “Engineering and Analysis of Fixed Priority Schedulers,” Software Eng., vol. 19, no. 9, 1993.
[3] C. Liu and J. Layland, “Scheduling Algorithms for Multiprogramming in a Hard Real-Time Environment,” ACM J., Jan. 1973.
[4] E. Thereska, J. Schindler, J. Bucy, B. Salmon, C.R. Lumb, and G.R. Ganger, “A Framework for Building Unobtrusive Disk Maintenance Applications,” Proc. Third Usenix Conf. File and Storage Technologies (FAST), Mar. 2004.
[5] R.T. Azuma, “Tracking Requirements for Augmented Reality,” Comm. ACM, vol. 36, no. 7, July 1993.
[6] Z. Dimitrijevic, R. Rangaswami, and E. Chang, “Design and Implementation of Semi-Preemptible IO,” Proc. Second Usenix Conf. File and Storage Technologies (FAST), Mar. 2003.
[7] Z. Dimitrijevic, R. Rangaswami, and E. Chang, “Preemptive Raid Scheduling,” Technical Report TR-2004-19, Univ. of California, Santa Barbara, Apr. 2004.
[8] Z. Dimitrijevic, R. Rangaswami, D. Watson, and A. Acharya, “Diskbench: User-Level Disk Feature Extraction Tool,” Technical Report TR-2004-18, Univ. of California, Santa Barbara, Apr. 2004.
[9] J. Schindler, J.L. Griffin, C.R. Lumb, and G.R. Ganger, “Track-Aligned Extents: Matching Access Patterns to Disk Drive Characteristics,” Proc. First Usenix Conf. File and Storage Technologies (FAST), Jan. 2002.
[10] S. Ghemawat, H. Gobioff, and S.-T. Leung, “The Google File System,” ACM Symp. Operating System Principles (SOSP), Oct. 2003.
[11] Z. Dimitrijevic, R. Rangaswami, and E. Chang, “The XTREAM Multimedia System,” Proc. IEEE Conf. Multimedia and Expo, Aug. 2002.
[12] S. Iyer and P. Druschel, “Anticipatory Scheduling: A Disk Scheduling Framework to Overcome Deceptive Idleness in Synchronous I/O,” Proc. 18th Symp. Operating Systems Principles, Sept. 2001.
[13] C. Ruemmler and J. Wilkes, “An Introduction to Disk Drive Modeling,” Computer, 1994.
[14] C.R. Lumb, J. Schindler, G.R. Ganger, and D.F. Nagle, “Towards Higher Disk Head Utilization: Extracting Free Bandwith from Busy Disk Drives,” Proc. Usenix Symp. Operating Systems Design and Implementation (OSDI), Oct. 2000.
[15] Seagate Tech nology, “Seagate's Sound Barrier Technology,” sound_barrier. pdf, Nov. 2000.
[16] E. Riedel, C. Faloutsos, G.R. Ganger, and D.F. Nagle, “Data Mining on an OLTP System (Nearly) for Free,” Proc. ACM SIGMOD, May 2000.
[17] D.M. Jacobson and J. Wilkes, “Disk Scheduling Algorithms Based on Rotational Position,” Technical Report HPL-CSP-91-7rev1, Hewlett-Packard Laboratories, Mar. 1991.
[18] P.M. Chen, E.K. Lee, G.A. Gibson, R.H. Katz, and D.A. Patterson, “RAID: High-Performance, Reliable Secondary Storage,” ACM Computing Surveys, vol. 26, no. 2, June 1994.
[19] J. Wilkes, R. Golding, C. Staelin, and T. Sullivan, “The HP AutoRAID Hierarchical Storage System,” ACM Trans. Computer Systems, vol. 14, no. 1, Feb. 1996.
[20] M. Mesnier, G.R. Ganger, and E. Riedel, “Object-Based Storage,” IEEE Comm. Magazine, Aug. 2003.
[21] Performance Evaluation Laboratory, Brigham Young Univ., “Trace Distribution Center,”, 2002.
[22] G.R. Ganger, B.L. Worthington, and Y.N. Patt, “The DiskSim Simulation Environment Version 2. 0 Reference Manual,” Reference Manual, Dec. 1999.
[23] S.J. Daigle and J.K. Strosnider, “Disk Scheduling for Multimedia Data Streams,” Proc. IS&T/SPIE, Feb. 1994.
[24] A. Molano, K. Juvva, and R. Rajkumar, “Guaranteeing Timing Constraints for Disk Accesses in RT-Mach,” Proc. IEEE Real Time Systems Symp., Dec. 1997.
[25] A. Thomasian, “Priority Queueing in RAID5 Disk Arrays with an NVS Cache,” Proc. IEEE Int'l Symp. Modeling, Analysis, and Simulation of Computer and Telecomm. Systems (MASCOTS), Jan. 1995.
[26] M. Aboutabl, A. Agrawala, and J.-D. Decotignie, “Temporally Determinate Disk Access: An Experimental Approach,” Technical Report CS-TR-3752, Univ. of Maryland, 1997.
[27] J. Schindler and G.R. Ganger, “Automated Disk Drive Characterization,” Technical Report CMU-CS-00-176, Carnegie Mellon Univ., Dec. 1999.
[28] N. Talagala, R.H. Arpaci-Dusseau, and D. Patterson, “Microbenchmark-Based Extraction of Local and Global Disk Characteristics,” technical report, Univ. of California, Berkeley, 1999.
[29] B.L. Worthington, G. Ganger, Y.N. Patt, and J. Wilkes, “Online Extraction of SCSI Disk Drive Parameters,” Proc. ACM Sigmetrics, May 1995.
[30] B.L. Worthington, G.R. Ganger, and Y.N. Patt, “Scheduling Algorithms for Modern Disk Drives,” Proc. ACM Sigmetrics, May 1994.
[31] L. Huang and T. Chiueh, “Implementation of a Rotation-Latency-Sensitive Disk Scheduler,” technical report, State Univ. of New York at Stony Brook, May 2000.
[32] C.R. Lumb, J. Schindler, and G.R. Ganger, “Freeblock Scheduling Outside of Disk Firmware,” Proc. First Usenix Conf. File and Storage Technologies (FAST), Jan. 2002.
[33] E. Chang and H. Garcia-Molina, “Bubbleup— Low Latency Fast-Scan for Media Servers,” Proc. Fifth ACM Multimedia Conf., Nov. 1997.
[34] C. Shahabi, S. Ghandeharizadeh, and S. Chaudhuri, “On Scheduling Atomic and Composite Multimedia Objects,” IEEE Trans. Knowledge and Data Eng., vol. 14, no. 2, Mar./Apr. 2002.
[35] P.J. Shenoy and H.M. Vin, “Cello: A Disk Scheduling Framework for Next Generation Operating Systems,” Proc. ACM Sigmetrics, June 1998.

Index Terms:
Index Terms- Storage, preemptible disk access, preemptive disk scheduling, real-time, QoS, disk IO preemption.
Zoran Dimitrijevic, Raju Rangaswami, Edward Y. Chang, "Systems Support for Preemptive Disk Scheduling," IEEE Transactions on Computers, vol. 54, no. 10, pp. 1314-1326, Oct. 2005, doi:10.1109/TC.2005.170
Usage of this product signifies your acceptance of the Terms of Use.