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CompSci 296.2 Self-Managing Systems. Shivnath Babu. Today. IBM’s LE arning O ptimizer (LEO) Oracle’s Automatic Database Diagnostic Monitor. Background. Declarative queries Query plans Query optimizer Indexes, index-AND’ing, materialization
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CompSci 296.2 Self-Managing Systems Shivnath Babu
Today • IBM’s LEarning Optimizer (LEO) • Oracle’s Automatic Database Diagnostic Monitor
Background • Declarative queries • Query plans • Query optimizer • Indexes, index-AND’ing, materialization • Statistics, e.g., Histograms, quantiles (percentile) • Assumptions made by query optimizer • Uniformity, inclusion, independence
LEO • Feedback-based learning • Inter-query
LEO • Feedback-based learning • Intra-query
Challenges • Stability • Detecting a problem • Deciding to respond to a problem • Dealing with bias, incompleteness, uncertainty
Oracle ADDM • Root-cause identification • Recommend fix • Characterize improvement
Oracle ADDM • DB-Time • Need common unit; DB-Time Vs. Wall-Clock time • DB-Time graph • Data collection • Time • Active Session History • Observe, Diagnose, Resolve • Experimental evaluation
Discussion • Relationship between the two papers? • Differences between the papers? • Can ADDM answer the What-if question on Page 3? • Dealing with concurrency • Accounting for DB-Time • Extending DB-Time • Experimental evaluation • Can we extend ADDM approach to 3-tier system? • Stability