Video: Qhov thib ob Namenode hauv Apache Hadoop yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Secondary NameNode hauv haoop ua yog ib qho tshwj xeeb tshwj xeeb ntawm cov hauv HDFS pawg uas nws lub luag haujlwm tseem ceeb yog los saib xyuas cov ntaub ntawv kaw lus metadata tam sim no ntawm npe . Nws tsis yog thaub qab npe . Nws tsuas yog checkpoints cov npe file system namespace.
Tsuas yog li ntawd, dab tsi yog qhov thib ob NameNode yog qhov hloov pauv rau Namenode?
Cov Secondary Namenode tas li nyeem cov ntaub ntawv los ntawm RAM ntawm lub Lub npe thiab sau nws rau hauv lub hard disk lossis cov ntaub ntawv kaw lus. Nws tsis yog ib hloov mus rau Namenode , yog li cov Lub npe ua tsis tiav, tag nrho Hadoop system poob.
Kuj Paub, yuav ua li cas thaum NameNode restarts? Tsuas yog thaum lub Lub npe yog rov pib dua , kho cov cav yog siv rau fsimage kom tau txais qhov tseeb snapshot ntawm cov ntaub ntawv kaw lus. Tab sis rov pib dua ntawm a Namenode tshwm sim tsis tshua muaj nyob rau hauv pawg ntau lawm uas qhia peb tias kho cov cav tuaj yeem loj hlob tuaj rau pawg, thaum twg Lub npe khiav rau lub sijhawm ntev.
Hauv qhov no, puas yog qhov thib ob NameNode yog tus thaub qab ntawm?
Backup Node : Hauv Secondary Namenode thiab Checkpoint Node , checkpoints yog tsim nyob rau hauv lawv lub zos cov ntaub ntawv systems los ntawm downloading fsimage thiab kho cov ntaub ntawv teev cia los ntawm active thawj npe thiab sib koom ua ke ob cov ntaub ntawv no thiab cov ntawv theej fsimage tshiab tau txais kev cawmdim ntawm lawv cov ntaub ntawv hauv zos.
NameNode hauv HDFS yog dab tsi?
NameNode yog lub hauv paus ntawm HDFS . Lub npeNode kuj hu ua tus Xib Hwb. Lub npeNode tsuas khaws cov metadata ntawm HDFS - cov ntoo directory ntawm tag nrho cov ntaub ntawv nyob rau hauv cov ntaub ntawv system, thiab taug qab cov ntaub ntawv nyob rau hauv pawg. Lub npeNode tsis khaws cov ntaub ntawv tiag tiag lossis dataset. Cov ntaub ntawv nws tus kheej tau khaws cia hauv DataNodes.
Pom zoo:
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Dab tsi yog qhov ntsuas thib ob hauv Google Analytics kev xeem?
Raws li Google Analytics kev txhawb nqa, "TheSecondary Dimension feature tso cai rau koj los txheeb xyuas qhov tseem ceeb thiab tom qab ntawd saib cov ntaub ntawv los ntawm qhov thib ob hauv tib lub rooj. Yog tias koj xaiv lub nroog thib ob ntawm Lub Nroog, tom qab ntawd koj pom cov nroog uas muaj kev thauj mus los ntawm qhov chaw pib. "