accumulo-notifications mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dylan Hutchison (JIRA)" <j...@apache.org>
Subject [jira] [Assigned] (ACCUMULO-3959) Confusing wording on BatchScanner javadoc
Date Mon, 24 Aug 2015 02:23:48 GMT

     [ https://issues.apache.org/jira/browse/ACCUMULO-3959?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Dylan Hutchison reassigned ACCUMULO-3959:
-----------------------------------------

    Assignee: Dylan Hutchison

> Confusing wording on BatchScanner javadoc
> -----------------------------------------
>
>                 Key: ACCUMULO-3959
>                 URL: https://issues.apache.org/jira/browse/ACCUMULO-3959
>             Project: Accumulo
>          Issue Type: Improvement
>          Components: docs
>    Affects Versions: 1.6.3, 1.7.0
>            Reporter: Dylan Hutchison
>            Assignee: Dylan Hutchison
>            Priority: Minor
>              Labels: docuentation
>             Fix For: 1.6.4, 1.7.1
>
>
> The following sentence in the [BatchScanner Javadoc|https://accumulo.apache.org/1.7/apidocs/org/apache/accumulo/core/client/BatchScanner.html]
has confused my colleagues into using Scanners and wondering why performance doesn't scale.
> bq. If you want to lookup a few ranges and expect those ranges to contain a lot of data,
then use the Scanner instead.
> Also regarding this next sentence, from what I see of the BatchScanner it will break
up "large Range objects" that span multiple extents (tablets) into multiple ranges, possibly
one for each tablet.
> bq. Use this when looking up lots of ranges and you expect each range to contain a small
amount of data.
> If the client is okay with unsorted order and it is okay with using multiple threads,
then isn't it always a better decision to use a BatchScanner than regular Scanner?  In the
worst case, one Range over a single row, the BatchScanner will perform the same as a regular
Scanner, ya?



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

Mime
View raw message