May I ask everyone some questions? I am importing data from MySQL into HBase via Sqoop command. The imported data table CustOrders, a total of 20,000,000 records (1739 MB) And Sqoop data import command as follows:
As mentioned above, I used Sqoop to import the relation table CustOrders from MySQL to HBase, but there are still many unreasonable results: (1) When using one mapper, more than 1 million records are imported in 7 hours, but when using 2 mappers, only 38,000 records are imported in 7 hours. (2) When two mappers are used, the data is imported into 38,000 records in 7 hours, but only 23,000 records are imported in 10.3 hours. (3) When using one mapper, more than one million records are imported for 7 hours of data import, and more than one million records are also imported for 99 hours of data import.
Is there any possible reasons behind it (or has the other opinions)?