the complete blog link is: http://zh.hortonworks.com/blog/blockcache-showdown-hbase/
2014-08-20 11:41 GMT+08:00 牛兆捷 <[email protected]>: > Hi all: > > I saw some interesting results from Hortonworks blog (block cache > <http://zh.hortonworks.com/wp-content/uploads/2014/03/perfeval_blockcache_v2.pdf> > ). > > In this result, the ratio of memory footprint to database size is held > fixed while > the absolute values are increased. > > In my mind, the performance should becomes worse for larger ratio as the > increase > of the absolute value. For example BucketCache#(tmpfs), the difference > between ratio (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0) becomes > larger as the increase of memory. > Actually, the result of ratio ( DB"1.5":"RAM"1.0) increase linearly, and > the result of ratio (DB"1.5":"RAM"1.0) exponentially. > > However, for BucketCache#(heap) and LruBlockCache, the result is out of my > expectation. > The curves of ratio (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0) both > increase exponentially, but the relative differences as the increase of > memory are not consistent. > Take LruBlockCache as an example, the difference of ratio > (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0) becomes smaller from 20 GB > to 50 GB, but becomes larger from 50 GB to 60 GB. > > How to analysis the cause of this result, any ideas? > > -- > *Regards,* > *Zhaojie* > > -- *Regards,* *Zhaojie*
