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https://issues.apache.org/jira/browse/HBASE-9769?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13796434#comment-13796434
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Lars Hofhansl commented on HBASE-9769:
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MAX_VERSIONS=1 (or a low number) can only be used to eliminate the NEXT_COL
seek (as that is use to seek past versions of the same column). It does not
indicate anything about the number of columns in a row, and hence we know
nothing about whether SEEK_NEXT_ROW or a series of SKIPs is better.
We need both, I think.
(MAX_VERSIONS is a hint in the sense that there temporarily can be more
versions in the memstore and/or distributed over various HFiles, only after a
major compaction will the number of versions actually be <= MAX_VERSIONS.)
> Improve performance of a Scanner with explicit column list when rows are
> small/medium size
> ------------------------------------------------------------------------------------------
>
> Key: HBASE-9769
> URL: https://issues.apache.org/jira/browse/HBASE-9769
> Project: HBase
> Issue Type: Improvement
> Components: Scanners
> Affects Versions: 0.98.0, 0.94.12, 0.96.0
> Reporter: Vladimir Rodionov
> Assignee: Vladimir Rodionov
> Attachments: 9769-0.94-sample1.txt, 9769-0.94-sample2.txt,
> 9769-0.94-sample.txt, 9769-94.txt
>
>
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