HBase预分区

seq 0 7 | awk '{printf("\\x%02x\\x%02x\n", $1/256, $1%256);}' | sort -R |head -3

create 'msgbox', '0', {SPLITS_FILE => 'splits.txt'}

create 't', {NAME => 'fww', VERSIONS => 1, COMPRESSION => 'SNAPPY', SPLITS => ['10','20','30']}

1：mkSplit.sh
#!/bin/sh
let step=65535/500
let i=1
let ret=0
while(( $i<=500 ))
do
        let ret=ret+step
        echo $ret
        let i=i+1
done

2： showSplit.sh

#!/bin/sh
sh mkSplit.sh | awk '{printf("\\x%02x\\x%02x\n", $1/256, $1%256);}'

3：使用

sh showSplit.sh >> split_500.txt

create 'rela_user_acct_relation', {MAX_FILESIZE => '10737418240',SPLITS_FILE => '/home/hdp/preSplit/split_500.txt'}, {NAME => 'd',  BLOOMFILTER => 'ROW',  VERSIONS => '1', COMPRESSION => 'LZO', MIN_VERSIONS => '0',  BLOCKSIZE => '65536', IN_MEMORY => 'false', BLOCKCACHE => 'true'}

分区算法的接口是SplitAlgorithm，

实现类是HexStringSplit和UniformSplit。

创建表使用预分区的时候可以参照这两个类的split(int numRegions)方法。可以设定first key 和last key。

bin/hbase org.apache.hadoop.hbase.util.RegionSplitter -c 60 -f f:d myTable HexStringSplit

其中f和d是family