[ 
https://issues.apache.org/jira/browse/OAK-4277?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Francesco Mari updated OAK-4277:
--------------------------------
    Fix Version/s:     (was: Segment Tar 0.0.4)
                   Segment Tar 0.0.6

> Finalise de-duplication caches
> ------------------------------
>
>                 Key: OAK-4277
>                 URL: https://issues.apache.org/jira/browse/OAK-4277
>             Project: Jackrabbit Oak
>          Issue Type: Task
>          Components: segment-tar
>            Reporter: Michael Dürig
>            Assignee: Michael Dürig
>              Labels: caching, compaction, gc, monitoring
>             Fix For: 1.6, Segment Tar 0.0.6
>
>
> OAK-3348 "promoted" the record cache to a de-duplication cache, which is 
> heavily relied upon during compaction. Now also node states go through this 
> cache, which can seen as one concern of the former compaction map (the other 
> being equality). 
> The current implementation of these caches is quite simple and served its 
> purpose for a POC for getting rid of the "back references" (OAK-3348). Before 
> we are ready for a release we need to finalise a couple of things though:
> * Implement cache monitoring and management
> * Make cache parameters now hard coded configurable
> * Implement proper UTs 
> * Add proper Javadoc
> * Fine tune eviction logic and move it into the caches themselves (instead of 
> relying on the client to evict items pro-actively)
> * Fine tune caching strategies: For the node state cache the cost of the item 
> is determined just by its position in the tree. We might want to take further 
> things into account (e.g. number of child nodes). Also we might want to 
> implement pinning so e.g. checkpoints would never be evicted. 
> * Finally we need to decide who should own this cache. It currently lives 
> with the {{SegmentWriter}}. However this is IMO not the correct location as 
> during compaction there is dedicated segment writer whose cache need to be 
> shared with the primary's segment writer upon successful completion. 



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to