[ 
https://issues.apache.org/jira/browse/YARN-796?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14127329#comment-14127329
 ] 

Craig Welch commented on YARN-796:
----------------------------------

This is a bit of a detail, but the current version of the code lowercases the 
nodelabels rather than respecting the given name.  I don't believe this is what 
we want.  The requirements do request case-insensitive comparison, but that is 
not the same as changing the case.  There are a few options which come to mind:

1. Switch to case insensitive Set's and Maps for managing the labels - TreeSet 
and TreeMap can be configured to operate in a case-insensitive fashion, I 
expect they would be OK to use for nodelables.
2. Gate label names on the way in to force consistent case while maintaining 
case - a Map with lc key and original case value could be used to keep all 
labels for a given set of letters a consistent case (the original)
3.  Drop the requirement for case insensitivity - I'm not sure of the 
reasoning, I assume it is to prevent mis-types, but I'm not sure it's really so 
important, and there are still many opportunities for mistyping labels, I'm not 
sure if protecting against this one case is worth the implementation 
cost/complexity or the loss of the original case as specified by the user. 

I suggest 3, FWIW

> Allow for (admin) labels on nodes and resource-requests
> -------------------------------------------------------
>
>                 Key: YARN-796
>                 URL: https://issues.apache.org/jira/browse/YARN-796
>             Project: Hadoop YARN
>          Issue Type: Sub-task
>    Affects Versions: 2.4.1
>            Reporter: Arun C Murthy
>            Assignee: Wangda Tan
>         Attachments: LabelBasedScheduling.pdf, 
> Node-labels-Requirements-Design-doc-V1.pdf, 
> Node-labels-Requirements-Design-doc-V2.pdf, YARN-796-Diagram.pdf, 
> YARN-796.node-label.consolidate.1.patch, YARN-796.node-label.demo.patch.1, 
> YARN-796.patch, YARN-796.patch4
>
>
> It will be useful for admins to specify labels for nodes. Examples of labels 
> are OS, processor architecture etc.
> We should expose these labels and allow applications to specify labels on 
> resource-requests.
> Obviously we need to support admin operations on adding/removing node labels.



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

Reply via email to