hbase-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HBASE-1460) Concurrent LRU Block Cache
Date Fri, 26 Jun 2009 22:05:47 GMT

    [ https://issues.apache.org/jira/browse/HBASE-1460?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12724735#action_12724735

stack commented on HBASE-1460:

Changed sizing to be percentage of max heap size; i.e. I changed the meaning of this configuration:

Added print out when LRU initialized:

2009-06-26 14:57:53,366 INFO org.apache.hadoop.hbase.regionserver.StoreFile: Allocating LruBlockCache
with maximum size 199.0m

Running tests now.  Patch looks good.  If tests pass, will commit since we need to burn this
puppy in before release.

> Concurrent LRU Block Cache
> --------------------------
>                 Key: HBASE-1460
>                 URL: https://issues.apache.org/jira/browse/HBASE-1460
>             Project: Hadoop HBase
>          Issue Type: Improvement
>          Components: io
>            Reporter: Jonathan Gray
>            Assignee: Jonathan Gray
>             Fix For: 0.20.0
>         Attachments: HBASE-1460-v1.patch, HBASE-1460-v2.patch, HBASE-1460-v3.patch, HBASE-1460-v4.patch,
> The LRU-based block cache that will be committed in HBASE-1192 is thread-safe but contains
a big lock on the hash map.  Under high load, the block cache will be hit very heavily from
a number of threads, so it needs to be built to handle massive concurrency.
> This issue aims to implement a new block cache with LRU eviction, but backed by a ConcurrentHashMap
and a separate eviction thread.  Influence will be drawn from Solr's ConcurrentLRUCache, however
there are major differences because solr treats all cached elements as equal size whereas
we are dependent on our HeapSize interface with realistic (though approximate) heap usage.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message