3. 测试的数据 10000 rows data are insert. take 37 s. 50000 rows data are insert. take 172 s. 100000 rows data are insert. take 351 s. 平均每秒钟写入270条记录,平均写入每条记录花费时间3.51ms 测试环境:两台物理机,两台虚拟机
6. Hbase建表 Number of Versions The number of row versions to store is configured per column family via HColumnDescriptor. The default is 3. This is an important parameter because as described in Chapter 9, Data Model section HBase does not overwrite row values, but rather stores different values per row by time (and qualifier). Excess versions are removed during major compactions. The number of versions may need to be increased or decreased depending on application needs.
7. Hbase建表 TTL : time to live 对于超过一定时间,需要清理数据的应用,会特别合适。 In_memory => true or false ,在region server block cache的分配使用上会有所不同。具体如何不同,研究完相关代码再补充。
24. RegionSplitter The RegionSplitter class provides several utilities to help in the administration lifecycle for developers who choose to manually split regions instead of having HBase handle that automatically. The most useful utilities are: Create a table with a specified number of pre-split regions Execute a rolling split of all regions on an existing table