Cov txheej txheem:

Dab tsi yog qhov kev teeb tsa tseem ceeb uas cov neeg siv yuav tsum tau qhia kom khiav MapReduce txoj haujlwm?
Dab tsi yog qhov kev teeb tsa tseem ceeb uas cov neeg siv yuav tsum tau qhia kom khiav MapReduce txoj haujlwm?

Video: Dab tsi yog qhov kev teeb tsa tseem ceeb uas cov neeg siv yuav tsum tau qhia kom khiav MapReduce txoj haujlwm?

Video: Dab tsi yog qhov kev teeb tsa tseem ceeb uas cov neeg siv yuav tsum tau qhia kom khiav MapReduce txoj haujlwm?
Video: Saib Mis paub Poj niam (hluas nkauj) tus yam ntxwv lub siab 2024, Kaum ib hlis
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Lub ntsiab configuration parameters uas cov neeg siv yuav tsum tau qhia rau hauv "MapReduce" lub moj khaum yog:

  • Txoj hauj lwm input qhov chaw nyob rau hauv lub faib cov ntaub ntawv system.
  • Txoj hauj lwm tso zis qhov chaw nyob rau hauv lub faib cov ntaub ntawv system.
  • Input format cov ntaub ntawv.
  • Tso zis hom ntaub ntawv.
  • Chav kawm uas muaj daim ntawv qhia ua haujlwm.
  • Chav kawm uas muaj qhov txo qis ua haujlwm.

Ntawm no, dab tsi yog qhov kev teeb tsa tseem ceeb hauv MapReduce program?

Lub ntsiab configuration tsis nyob rau hauv "MapReduce" lub moj khaum yog:

  • Nkag siab qhov chaw ntawm Cov Haujlwm hauv cov ntaub ntawv faib tawm.
  • Tso tawm qhov chaw ntawm Cov Haujlwm hauv cov ntaub ntawv faib tawm.
  • Cov ntaub ntawv input.
  • Cov ntaub ntawv tso zis ntau lawm.
  • Cov chav kawm uas muaj daim ntawv qhia ua haujlwm.
  • Cov chav kawm uas muaj qhov txo qis ua haujlwm.

Ib tug kuj yuav nug, dab tsi yog cov tsis muaj mappers thiab reducers? Plaub qhov ntsuas rau mappers yog:

  • LongWritable (input)
  • ntawv (input)
  • text (intermediate output)
  • IntWritable (cov zis nruab nrab)

Tsis tas li cov lus nug yog, cov khoom tseem ceeb ntawm MapReduce txoj haujlwm yog dab tsi?

  • Cov chav kawm tsav tsheb tseem ceeb uas muab cov kev teeb tsa ua haujlwm.
  • Mapper chav kawm uas yuav tsum txuas ntxiv org. apache. haoop ua. mapreduce. Mapper chav kawm thiab muab kev siv rau daim ntawv qhia () txoj kev.
  • Cov chav kawm txo qis uas yuav tsum txuas ntxiv org. apache. haoop ua. mapreduce. Cov chav kawm reducer.

Dab tsi yog partitioner thiab nws yuav pab tau li cas hauv MapReduce txoj haujlwm?

Muab faib hauv MapReduce txoj haujlwm execution tswj lub partitioning ntawm cov yawm sij ntawm daim ntawv qhia nruab nrab-tso tawm. Nrog rau pab ntawm hash muaj nuj nqi, qhov tseem ceeb (los yog ib tug subset ntawm tus yuam sij) derives muab faib . Cov ntaub ntawv uas muaj tus nqi tseem ceeb tib yam mus rau hauv tib yam muab faib (hauv txhua daim ntawv qhia).

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