MSN 数学媒体与信息存储 1/27 Zhuo Liu, Fei Wu, Xiao Qin, Changsheng Xie, Jian Zhou, and Jianzong Wang TRACER: A Trace Replay Tool to Evaluate Energy-Efficiency of Mass Storage Systems WNLO, Huazhong University of Science and Technology; Computer Science Department, Auburn University

MSN 数学媒体与信息存储 2/27 Outline  I. Motivation  Why do we need TRACER?  II. Architecture  What does TRACER consist of?  How does TRACER work and look like?  III. Trace-replay control scheme  How does TRACER control load intensity?  IV. Measurement  How well does TRACER work?  V. Conclusion and future work

MSN 数学媒体与信息存储 3/27 I Motivation  New energy conservation techniques in storage systems constantly spring up:  such as MAID, DRPM, PDC…  Lack of systematic and uniform way to evaluate them:  present benchmarks and standards are most for CPU-intensive applications

MSN 数学媒体与信息存储 4/27 Current power-aware techniques

MSN 数学媒体与信息存储 5/27 Energy-efficiency Standards  SPEC (CPU-intensive)  Metric: Java_ops/Watt  SUN swap (CPU-intensive)  Metric: Performance/(Space*Watt)  Joule Sort (CPU-intensive)  Metric: Sort_ops/Joule  Energy Star  SNIA green  Classification of storage devices  Standards mainly for idle-mode tests

MSN 数学媒体与信息存储 6/27 Power increases with load intensity SNIA-Green

MSN 数学媒体与信息存储 7/27 What should TRACER do? Test the power consumptions Produce different modes of IO load Regulate IO load intensity: 10%-100% Metrics: to evaluate energy-efficiency TRACER

MSN 数学媒体与信息存储 8/27 II. Architecture of TRACER  TRACER consists of four parts: Evaluation host Workload generator Power analyzer Storage systems under test

MSN 数学媒体与信息存储 9/27 What does TRACER consist of?

MSN 数学媒体与信息存储 10/27 How is TRACER implemented?

MSN 数学媒体与信息存储 11/27 GUI of TRACER

MSN 数学媒体与信息存储 12/27 III. Trace-replay control scheme The structure of a blocktrace file

MSN 数学媒体与信息存储 13/27 Load-control algorithm for trace replay

MSN 数学媒体与信息存储 14/27 IV. Measurement: environment

MSN 数学媒体与信息存储 15/27 Measurement: hardware connects

MSN 数学媒体与信息存储 16/27 Measurement : traces  Three types of traces:  125 traces we connected using IOmeter Request size: 512B, 4KB, 16KB, 64KB, 1MB Random/sequential%: 0%,25%, 50%, 75%,100% Read/write%: 0%, 25%,50%,75%, 100%  HP lab: cello 96 and cello 99  The web server trace (FAST’09-BORG)

MSN 数学媒体与信息存储 17/27 Measurement : evaluation metrics  IO Throughput/Power Consumption  IOPS/Watt  MBPS/Kilowatt

MSN 数学媒体与信息存储 18/27 V. Measurement: results  1. Accuracy of load control for 125 traces  Accuracy % =Measured intensity% / configured%  2. How Energy-efficiency is influenced  By load intensity  By random%  By read%  3. Accuracy for Real traces  HP lab cello99 cello96, web server traces

MSN 数学媒体与信息存储 19/27 Accuracy of load control

MSN 数学媒体与信息存储 20/27 E-E influenced by load%

MSN 数学媒体与信息存储 21/27 E-E influenced by random%

MSN 数学媒体与信息存储 22/27 E-E influenced by read%

MSN 数学媒体与信息存储 23/27 Load control for real trace

MSN 数学媒体与信息存储 24/27 Accuracy of load control for real trace

MSN 数学媒体与信息存储 25/27 Conclusion and Future Work  1 TRACER is accurate, efficient and useful.  2 Storage system is more energy-efficient under higher load intensity, under lower random rate.  3 As temperature influences system’s performance and power, it’s necessary to add temperature as part of evaluation metrics.

MSN 数学媒体与信息存储 26/27 Add Temperature metrics Temp sensor

MSN 数学媒体与信息存储 27/27 Any question?