Haven't tried yet only one thread 10 regions servers, total 2555 regions. I am just new to HBase and not sure what exactly the block cache mean, here's the configuration i can see from the CDH HBase master UI: <name>hbase.rs.cacheblocksonwrite</name> <value>false</value> <source>hbase-default.xml</source>
<name>hbase.offheapcache.percentage</name> <value>0</value> <source>hbase-default.xml</source> <name>hfile.block.cache.size</name> <value>0.0</value> <source>programatically</source> Table description: {NAME => 'userdigest', coprocessor$3 => 'hdfs://agrant/user/tracking/userdigest/copro cessor/endpoint_0.0.17.jar|com.agrantsem.data.userdigest.endpoint.UserdigestEndPoint| 1001|', coprocessor$2 => '|org.apache.hadoop.hbase.coprocessor.AggregateImplementatio n||', FAMILIES => [{NAME => 'cf', DATA_BLOCK_ENCODING => 'NONE', BLOOMFILTER => 'ROWC OL', REPLICATION_SCOPE => '0', VERSIONS => '1', COMPRESSION => 'LZ4', MIN_VERSIONS => '0', TTL => '2147483647', KEEP_DELETED_CELLS => 'false', BLOCKSIZE => '65536', IN_ME MORY => 'false', ENCODE_ON_DISK => 'true', BLOCKCACHE => 'true'}]} leiwang...@gmail.com From: Esteban Gutierrez Date: 2014-08-13 15:59 To: user@hbase.apache.org Subject: Re: Any fast way to random access hbase data? Hello Lei, Have you tried a larger batch size? how many threads or tasks are you using to fetch data? could you please describe a little bit more your HBase cluster? e.g. how many region servers, how many regions per RS? whats the hit ratio of the block cache? any chance for you to share the table schema? cheers, esteban. -- Cloudera, Inc. On Wed, Aug 13, 2014 at 12:34 AM, leiwang...@gmail.com <leiwang...@gmail.com > wrote: > > I have a hbase table with more than 2G rows. > Every hour there comes 5M~10M row ids and i must get all the row info from > the hbase table. > But even I use the batch call(1000 row ids as a list) as described here > > http://stackoverflow.com/questions/13310434/hbase-api-get-data-rows-information-by-list-of-row-ids > > It takes about 1 hour. > Any other way to do this more quickly? > > Thanks, > Lei > > > leiwang...@gmail.com >