[
https://issues.apache.org/jira/browse/HBASE-5401?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14269155#comment-14269155
]
Oliver Meyn commented on HBASE-5401:
------------------------------------
I've just run it against 0.98.6 (so, for the first time in 2 years) and it
appears to be generating the same 10x # of splits, and therefore mappers, more
than I would expect. The final rowcount looks fine though (ie hbase pe
sequentialWrite 1 produces 10 mappers but total 1M rows). My original patch was
just removing that outer loop, which I think would still work.
But, I think the chances are good that I've just misunderstood something - with
all those magical 10's in there I'm sure it's not a surprise to the original
dev that there are 10 mappers for every 1 on the command line. Maybe it's just
a documentation change needed?
> PerformanceEvaluation generates 10x the number of expected mappers
> ------------------------------------------------------------------
>
> Key: HBASE-5401
> URL: https://issues.apache.org/jira/browse/HBASE-5401
> Project: HBase
> Issue Type: Bug
> Components: test
> Reporter: Oliver Meyn
>
> With a command line like 'hbase org.apache.hadoop.hbase.PerformanceEvaluation
> randomWrite 10' there are 100 mappers spawned, rather than the expected 10.
> The culprit appears to be the outer loop in writeInputFile which sets up 10
> splits for every "asked-for client". I think the fix is just to remove that
> outer loop.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
