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https://issues.apache.org/jira/browse/MAPREDUCE-706?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12743468#action_12743468
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Tsz Wo (Nicholas), SZE commented on MAPREDUCE-706:
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The design doc is very nice (especially, it was typeset by tex)!

Some suggestions for future works:
- In hadoop, fs usually refers to FileSystem.  "fsdesigndoc" sounds like 
FileSystem design doc.  I think we should prevent overloading the term "fs".
- The tex file needs a license header.
- We do not have pdf files under ./src before.  "fsdesigndoc.pdf" is the first. 
 I think the correct approach is to generate the pdf file by "ant docs".  
However, it may not be easy to do so.

> Support for FIFO pools in the fair scheduler
> --------------------------------------------
>
>                 Key: MAPREDUCE-706
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-706
>             Project: Hadoop Map/Reduce
>          Issue Type: New Feature
>          Components: contrib/fair-share
>            Reporter: Matei Zaharia
>            Assignee: Matei Zaharia
>             Fix For: 0.21.0
>
>         Attachments: fsdesigndoc.pdf, fsdesigndoc.tex, mapreduce-706.patch, 
> mapreduce-706.v1.patch, mapreduce-706.v2.patch, mapreduce-706.v3.patch, 
> mapreduce-706.v4.patch, mapreduce-706.v5.patch
>
>
> The fair scheduler should support making the internal scheduling algorithm 
> for some pools be FIFO instead of fair sharing in order to work better for 
> batch workloads. FIFO pools will behave exactly like the current default 
> scheduler, sorting jobs by priority and then submission time. Pools will have 
> their scheduling algorithm set through the pools config file, and it will be 
> changeable at runtime.
> To support this feature, I'm also changing the internal logic of the fair 
> scheduler to no longer use deficits. Instead, for fair sharing, we will 
> assign tasks to the job farthest below its share as a ratio of its share. 
> This is easier to combine with other scheduling algorithms and leads to a 
> more stable sharing situation, avoiding unfairness issues brought up in 
> MAPREDUCE-543 and MAPREDUCE-544 that happen when some jobs have long tasks. 
> The new preemption (MAPREDUCE-551) will ensure that critical jobs can gain 
> their fair share within a bounded amount of time.

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