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https://issues.apache.org/jira/browse/HBASE-15181?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15127314#comment-15127314
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Clara Xiong commented on HBASE-15181:
-------------------------------------
As to the second question: my implementation sorts store files by max
timestamp. It is desirable not to compact non-contiguous range of store files
to maximize the scan performance by reducing time range overlap.
As to the more generic question about out-of-order data streams, they are
assigned to the compaction windows based on their max time stamps, not sequence
id. We have to pay some scan performance penalty only if the flush file
contains much wider time range compared to the compaction windows. A generic
solution for this would be splitting off data out of compaction window using
multiple output for compactor. As stated in the design spec, we don't see
enough benefit for this solution, yet.
> A simple implementation of date based tiered compaction
> -------------------------------------------------------
>
> Key: HBASE-15181
> URL: https://issues.apache.org/jira/browse/HBASE-15181
> Project: HBase
> Issue Type: New Feature
> Components: Compaction
> Reporter: Clara Xiong
> Assignee: Clara Xiong
> Fix For: 2.0.0
>
> Attachments: HBASE-15181-v1.patch, HBASE-15181-v2.patch
>
>
> This is a simple implementation of date-based tiered compaction similar to
> Cassandra's for the following benefits:
> 1. Improve date-range-based scan by structuring store files in date-based
> tiered layout.
> 2. Reduce compaction overhead.
> 3. Improve TTL efficiency.
> Perfect fit for the use cases that:
> 1. has mostly date-based date write and scan and a focus on the most recent
> data.
> 2. never or rarely deletes data.
> Out-of-order writes are handled gracefully so the data will still get to the
> right store file for time-range-scan and re-compacton with existing store
> file in the same time window is handled by ExploringCompactionPolicy.
> Time range overlapping among store files is tolerated and the performance
> impact is minimized.
> Configuration can be set at hbase-site or overriden at per-table or
> per-column-famly level by hbase shell.
> Design spec is at
> https://docs.google.com/document/d/1_AmlNb2N8Us1xICsTeGDLKIqL6T-oHoRLZ323MG_uy8/edit?usp=sharing
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