简介:Inacomputationalgrid,jobsmustadapttothedynamicallychangingheterogeneousenvironmentwithanobjectiveofmaintainingthequalityofservice.Inordertoenableadaptiveexecutionofmultiplejobsrunningconcurrentlyinacomputationalgrid,weproposeanintegratedperformance-basedresourcemanagementframeworkthatissupportedbyamulti-agentsystem(MAS).Themulti-agentsysteminitiallyallocatesthejobsontodifferentresourceprovidersbasedonaresourceselectionalgorithm.Later,duringruntime,ifperformanceofanyjobdegradesorqualityofservicecannotbemaintainedforsomereason(resourcefailureoroverloading),themulti-agentsystemassiststhejobtoadapttothesystem.Thispaperfocusesonapartofourframeworkinwhichadaptiveexecutionfacilityissupported.Adaptiveexecutionfacilityisavailedbyreallocationandlocaltuningofjobs.Mobile,aswellasstaticagentsareemployedforthispurpose.Thepaperprovidesasummaryofthedesignandimplementationanddemonstratestheefficiencyoftheframeworkbyconductingexperimentsonalocalgridtestbed.
简介:LuYunrejoicesthatshedidnothesitatetotakethejobasacommunitypatrolayearago."HadIrefusedtotakeupthejob,therewouldhavebeennoopportunityatalltofindajobnow,"shesaid.In2001,theDaliancitygovernmentboughtanumberofjobsofpublicwelfareinnature,includingpatrolsincommunities.However,manypeoplewerereluctanttotakethematthetime,leavingseveralhundredvacancies.LuYun,48,waslaidoffbytheDalianDepartmentStorefouryearsago.Sheappliedandwasgiventhejob.Althoughthemonthlysalaryisonly400yuan,shetooktolikeit."Icanenjoyold-ageinsuranceandmedicalinsurance,"
简介:Thispaperconsiderssingle-machineschedulingproblemsingrouptechnologywiththejobs'processingtimesbeingsimplelinearfunctionsoftheirstarttimes.Theobjectivefunctionsaretheminimizingofmakespanandtotalweightedcompletiontime.SomeoptimalconditionsandalgorithmsaregivenandthefactthattheproblemoftotalweightedcompletiontimesisNP-hardisproved.
简介:Thispaperstudiesonlineschedulingofjobswithkindreleasetimesonasinglemachine.Here“kindreleasetime”meansthatinonlinesetting,nojobscanbereleasedwhenthemachineisbusy.EachjobJhasakindreleasetimer(J)≥0,aprocessingtimep(J)>0andadeadlined(J)>0.Thegoalistodetermineaschedulewhichmaximizestotalprocessingtime(∑p(J)E(J))ortotalnumber(∑E(J))oftheacceptedjobs.Forthefirstobjectivefunction∑p(J)E(J),wefirstpresentalowerbound√2,andthenprovideanonlinealgorithmLEJwithacompetitiveratioof3.Thisisthefirstdeterministicalgorithmfortheproblemwithaconstantcompetitiveratio.Whenp(J)∈{1,k},k>1isarealnumber,wefirstpresentalowerboundminf(1+k)/k,2k/(1+k)g,andthenweshowthatLEJhasacompetitiveratioof1+┌k┐=k.Inparticular,whenalltheklengthjobshavetightdeadlines,wefirstpresentalowerboundmax{4=(2+k),1}(for∑p(J)E(J))and4/3(for∑E(J)).ThenweprovethatLEJis┌k┐/k-competitivefor∑p(J)E(J)andweprovideanonlinealgorithmHwithacompetitiveratioof2┌k┐/(┌k┐+1)forthesecondobjectivefunction∑E(J).