[ 
https://issues.apache.org/jira/browse/HBASE-17819?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

stack updated HBASE-17819:
--------------------------
    Status: In Progress  (was: Patch Available)

Moving to 'resume progress'.  This ready to go [~anoop.hbase] ?

> Reduce the heap overhead for BucketCache
> ----------------------------------------
>
>                 Key: HBASE-17819
>                 URL: https://issues.apache.org/jira/browse/HBASE-17819
>             Project: HBase
>          Issue Type: Sub-task
>          Components: BucketCache
>            Reporter: Anoop Sam John
>            Assignee: Anoop Sam John
>            Priority: Critical
>             Fix For: 2.0.0
>
>         Attachments: HBASE-17819_V1.patch, HBASE-17819_V2.patch, 
> HBASE-17819_V3.patch
>
>
> We keep Bucket entry map in BucketCache.  Below is the math for heapSize for 
> the key , value into this map.
> BlockCacheKey
> ---------------
> String hfileName  -  Ref  - 4
> long offset  - 8
> BlockType blockType  - Ref  - 4
> boolean isPrimaryReplicaBlock  - 1
> Total  =  12 (Object) + 17 = 29
> BucketEntry
> ------------
> int offsetBase  -  4
> int length  - 4
> byte offset1  -  1
> byte deserialiserIndex  -  1
> long accessCounter  -  8
> BlockPriority priority  - Ref  - 4
> volatile boolean markedForEvict  -  1
> AtomicInteger refCount  -  16 + 4
> long cachedTime  -  8
> Total = 12 (Object) + 51 = 63
> ConcurrentHashMap Map.Entry  -  40
> blocksByHFile ConcurrentSkipListSet Entry  -  40
> Total = 29 + 63 + 80 = 172
> For 10 million blocks we will end up having 1.6GB of heap size.  
> This jira aims to reduce this as much as possible



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to