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https://issues.apache.org/jira/browse/HBASE-9000?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13813676#comment-13813676
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Chao Shi commented on HBASE-9000:
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Hi [~zjushch],
bq. How to decide the config value?
I think most users should use the default value. This patch optimize
performance on scenario that reseek on MemStore is the bottleneck, for example,
scan with a filter that skips a lot of KVs. In this case, you need to tweak
this value and make sure linear seeks happen rather than reseeks (i.e.. set
this value to be greater than #versions in MemStore, if you are using
SEEK_NEXT_COL). As most users don't have much versions per KV in their
MemStore, I think the default value should play well.
bq. IMPO, the new code in MemStore seems not friendly
Could you please explain more on what can be improved?
> Linear reseek in Memstore
> -------------------------
>
> Key: HBASE-9000
> URL: https://issues.apache.org/jira/browse/HBASE-9000
> Project: HBase
> Issue Type: Improvement
> Affects Versions: 0.89-fb
> Reporter: Shane Hogan
> Priority: Minor
> Fix For: 0.89-fb
>
> Attachments: hbase-9000-benchmark-program.patch,
> hbase-9000-port-fb.patch, hbase-9000.patch
>
>
> This is to address the linear reseek in MemStoreScanner. Currently reseek
> iterates over the kvset and the snapshot linearly by just calling next
> repeatedly. The new solution is to do this linear seek up to a configurable
> maximum amount of times then if the seek is not yet complete fall back to
> logarithmic seek.
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