CS514: Intermediate Course in Operating SystemsSystems of SystemsScale of GTE’s (Verizon’s) IT EnvironmentMagic bulletsSlide 5What’s the threat?Real world “issue?”Why IBM created Autonomic Computing InitiativeTechnical and Social IssuesIs Autonomic Computing Hopeless?Lesson from Y2K?Strange robustnessFrom Shakespeare in Love.CS514: Intermediate Course in Operating SystemsProfessor Ken BirmanVivek Vishnumurthy: TASystems of SystemsLast week we looked briefly at issues that arise in systems of systemsWe focused on real-time because we’ve been on that theme for a few lecturesBut building these sorts of complex, interconnected systems raise other kinds of very serious issuesScale of GTE’s (Verizon’s) IT Environment$1.2 billion/year IT expense> 5000 ISs> 1.5 petabytes operational dataMagic bulletsA very common pattern in computing, especially in the business worldYou are spending a fortune on somethingTechnology is the problemMost of that money is spent because a technology is somehow inadequateThen along comes a (snake oil) salesman with “a radical advance”!And you leap because the consequence of being left behind is too horrible to contemplateMagic bulletsWhen a vampire is stalking the castle, loading your gun with magic silver bullets can have irresistible appeal(especially to management!)What’s the threat?Enormous complexity of modern distributed computing systems is overwhelming organizational resourcesPeople needed toInstall/configure software, hardwareDiagnose problemsRepair things that aren’t working rightReal world “issue?”System administration can be overwhelmingly hardTalk by Michael Brodie focuses on this… http://www.cs.cornell.edu/Courses/cs514/2007sp/brodie.pdf(visit Brodie materials here!)Why IBM created Autonomic Computing InitiativeAutonomic Computing represents an exciting new research direction in computing. IBM believes that the spiraling cost of managing the increasing complexity of computing systems is one of the biggest single issues threatening to undermine the future growth and societal benefits of information technology, and proposes a solution inspired by the human body: autonomic computing. The goal is to create computing networks and systems that -- like the biological analog -- hide complexity from the user and deliver much greater value than today's systems can. These new systems need to be self-managing, self-configuring, self-healing, self-protecting, and continuously self-optimizing.Technical and Social IssuesRepresent nominal systemCapture current stateDiagnose problemsPlan responseCarry out repair strategyEvaluate outcome…Does anyone have any idea what the system looks like?Are the components “instrumentable”?Faults cascade: How can we construct fault-trees?How long will it take for the repair to occur?Is Autonomic Computing Hopeless?Strictly speaking: yes. The problem can’t be solvedBut we can certainly improve systemsNeed new services to capture stateRoutine attention to robustnessAvoid tighter-than-needed coupling of componentsLesson from Y2K?People reasoned thatSystems are complex and interdependentIf many fail at same time, results will cascade worldwideAnd society as we know it will end!But Y2K came “not with a bang, but a whimper”Indian outsourcing companies claim responsibility but some people doubt this explanation!Strange robustnessSocial engineering forces heavily used systems to become robustPeople tend to focus on and improve components that often cause disruptive failuresCauses systems to be much more robustness than we can explainFrom Shakespeare in Love.Lambert holding Henslowe’s feet to the fireHENSLOWE Mr. Fennyman, let me explain about the theatre business. (they stop). The natural condition is one of insurmountable obstacles on the road to imminent disaster. Believe me, to be closed by the plague is a bagatelle in the ups and downs of owning a theatre. FENNYMAN So what do we do? HENSLOWE Nothing. Strangely enough, it all turns out well. FENNYMAN How? HENSLOWE I don't know. It's a mystery. LAMBERT (dumbly) Should I kill him, Mr. Fennyman?A din is heard in the background. A messenger, ringing a bell, is running though the street. MESSENGER The theatres are reopened. By order of the Master of the Revels, the theatres are
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