If BlockCache is on, the block will be cached in memory. Please see documents about blockcache, http://hbase.apache.org/book.html#block.cache
2016-06-17 8:57 GMT+08:00 WangYQ <[email protected]>: > > > I set all user tables with blockCache on, but set the IN_MEMORY conf to > false > > > > > > > > > At 2016-06-16 18:18:44, "Heng Chen" <[email protected]> wrote: > >bq. if we do not set any user tables IN_MEMORY to true, then the whole > >hbase just need to cache hbase:meta data to in_memory LruBlockCache. > > > >You set blockcache to be false for other tables? > > > >2016-06-16 16:21 GMT+08:00 WangYQ <[email protected]>: > > > >> in hbase 0.98.10, if we use LruBlockCache, and set regionServer's max > heap > >> to 10G > >> in default: > >> the size of in_memory priority of LruBlockCache is : > >> 10G * 0.4 * 0.25 = 1G > >> > >> > >> 0.4: hfile.block.cache.size > >> 0.25: hbase.lru.blockcache.memory.percentage > >> > >> > >> if we do not set any user tables IN_MEMORY to true, then the whole hbase > >> just need to cache hbase:meta data to in_memory LruBlockCache. > >> hbase:meta does not split , so just need one regionServer to cache, so > >> there is some waste in blockCache > >> > >> > >> i think the regionServer open hbase:meta need to set in_memory > >> LruBlockCache to a certain size > >> other regionServer set hbase.lru.blockcache.memory.percentage to 0, do > not > >> need to allocate in_memory LruBlockCache. >
