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Vladimir Rodionov commented on HBASE-11425: ------------------------------------------- I am quite skeptical to all this idea ... Here is why: Off heap cache can store blocks in a compressed form. It means that you won't be able to back HFileBlock by a such compressed block - you have to decompress it first. From performance point of view it does not matter whether you do this into direct BB (new approach) or into a byte array-backed BB (existing). Am I missing anything? > Cell/DBB end-to-end on the read-path > ------------------------------------ > > Key: HBASE-11425 > URL: https://issues.apache.org/jira/browse/HBASE-11425 > Project: HBase > Issue Type: Umbrella > Components: regionserver, Scanners > Affects Versions: 0.99.0 > Reporter: Anoop Sam John > Assignee: Anoop Sam John > Attachments: Offheap reads in HBase using BBs_final.pdf > > > Umbrella jira to make sure we can have blocks cached in offheap backed cache. > In the entire read path, we can refer to this offheap buffer and avoid onheap > copying. > The high level items I can identify as of now are > 1. Avoid the array() call on BB in read path.. (This is there in many > classes. We can handle class by class) > 2. Support Buffer based getter APIs in cell. In read path we will create a > new Cell with backed by BB. Will need in CellComparator, Filter (like SCVF), > CPs etc. > 3. Avoid KeyValue.ensureKeyValue() calls in read path - This make byte copy. > 4. Remove all CP hooks (which are already deprecated) which deal with KVs. > (In read path) > Will add subtasks under this. -- This message was sent by Atlassian JIRA (v6.3.4#6332)