Hi! We are using HBase 0.92.1-cdh4.1.1. To import data the only way we use is bulk load. And our common access pattern is sequential scans of different parts of the tables.
Since that we are considering to disable block cache by setting hbase.block.cache.size to zero. But We've found following in HBase book ( http://hbase.apache.org/book/important_configurations.html): "Do not turn off block cache (You'd do it by setting hbase.block.cache.size to zero). Currently we do not do well if you do this because the regionserver will spend all its time loading hfile indices over and over again. If your working set it such that block cache does you no good, at least size the block cache such that hfile indices will stay up in the cache (you can get a rough idea on the size you need by surveying regionserver UIs; you'll see index block size accounted near the top of the webpage)." Another thing we consider to reduce is memstore size by tuning following options hbase.regionserver.global.memstore.upperLimit and hbase.regionserver.global.memstore.lowerLimit. So, my questions are: Does it make sense to touch these options in our case? Is this memory reserved or other processes inside regionserver can use it? Thanks in advance! -- Best Regards Ivan Tretyakov Deployment Engineer Grid Dynamics +7 812 640 38 76 Skype: ivan.v.tretyakov www.griddynamics.com itretya...@griddynamics.com
