accumulo-notifications mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Sean Busbey (JIRA)" <>
Subject [jira] [Updated] (ACCUMULO-884) Take advantage of short circuit read for local files
Date Mon, 21 Apr 2014 17:50:17 GMT


Sean Busbey updated ACCUMULO-884:

    Priority: Major  (was: Minor)

The deliverables to close would be:

* Performance #s for some workload(s) as justification
* User manual addendum on configuration changes needed in HDFS and/or Accumulo (ala [HBase's

* logs or Monitor changes to show short circuit presence in running instance

I'm putting the priority back at Major because the performance impact on HBase was significant.

> Take advantage of short circuit read for local files
> ----------------------------------------------------
>                 Key: ACCUMULO-884
>                 URL:
>             Project: Accumulo
>          Issue Type: Sub-task
>          Components: docs
>            Reporter: Billie Rinaldi
> This is a new feature in hadoop 1.0.x and some versions of 0.22 and 0.23.  It allows
a client to read directly from disk instead of through a DataNode when the data is stored
locally.  Enabling it involves setting two configuration parameters, the first in hdfs-site.xml
and the second in accumulo-site.xml.  We should make sure this works with Accumulo and recommend
it in the documentation.
> - dfs.block.local-path-access.user is the key in datanode configuration to specify the
user allowed to do short circuit read.
> - is the key to enable short circuit read at the client
side configuration.
> See HDFS-2246 and for more information.

This message was sent by Atlassian JIRA

View raw message