HW4BufferManager：hw4缓冲区管理

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1、HW4:BufferManagerInstructors:WinstonHsu,Hao-HuaChuFall2009ArchitectureofaDBMSQueryQueryOptimizationandExecutionDBRelationOperatorsFileandAccessMethodsBufferManagementDiskSpaceManagementBufferManagerSimpleBufferManagerStructurePagesinthebufferpoolisnotorderedinanywayHashtabletofig

2、ureoutwhatframeagivendiskpageoccupiesLove/HatebufferreplacealgorithmOperationsbringadiskpageintothebufferpoolandpinitunpinapageinthebufferpoolallocate/de-allocatepagesondiskflush/flushallbufferpage(s)intothediskpageBufferManagerMemoryStructureFrameDescpageNodirtyFlagpin_countBu

3、fferPageDescriptionnumbufPageBufferPoolBufferHashTableHTSIZEpageNoframeNo*next…………Love/HateReplacementupperleveluserhintsthebuffermanagerthatthepageislovedorhated.Replacehatedpagesfirst,thenlovedpages.MRUlistforthehatedpages,LRUlistforthelovedpages“Loveconquershate“Functions(inbu

4、f.handbuf.C)BufMgrInitializesbuffermanager:createbufferpool,bufferpooldescription,hashtable….etc.Malloc,calloc…..pinPage,unpinPage,newPage,freePage,flushPage,flushAllPagesUseMinibaseAPIYourownfunctions(ifneeded)ForhashtableandreplacementpolicyMinibaseAPIsPageStatusMINIBASE_DB->re

5、ad_page(PageIdpageno,Page*pageptr)StatusMINIBASE_DB->write_page(PageIdpageno,Page*pageptr)StatusMINIBASE_DB->allocate_page(PageId&start_page_num,intrun_size=1)StatusMINIBASE_DB->deallocate_page(PageIdstart_page_num,intrun_size=1)Errorshandlingstatus=MINIBASE_DB->write_page(pageid

6、,&bufPool[i]);if(status!=OK){//status:OKorFAIL//yourownerrormessage}GetStartedReadthePDFfordetaildescription.Groupassignment(atmost2people/group)DownloadBufMgrforsourcecode.ReadREADME.firstbeforeyoustrat.Postyourquestionsonptt.cc/CSIE_DBMS.MinibasehomepageandGoogle