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https://issues.apache.org/jira/browse/CRUNCH-368?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13954661#comment-13954661
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Josh Wills commented on CRUNCH-368:
-----------------------------------
@Chao-- the only line I don't quite get is this one, in the new Comparator impl:
if (written1 != written2) {
return written1 - written2;
}
is it necessarily the case that we should prefer the shorter written value in
the case that both of the fields are non-null? That doesn't seem obvious to me.
> TupleWritable.Comparator
> ------------------------
>
> Key: CRUNCH-368
> URL: https://issues.apache.org/jira/browse/CRUNCH-368
> Project: Crunch
> Issue Type: Improvement
> Components: Core
> Affects Versions: 0.10.0, 0.8.3
> Reporter: Chao Shi
> Assignee: Chao Shi
> Attachments: crunch-368 benchmark.pdf, crunch-368.patch, gen_data.py
>
>
> This patch should improve comparison performance on TupleWritables. It saves
> the deserialization overhead. It is particularly useful when the input tuple
> are large, e.g. contains long strings.
> Please note that this changes the binary format of TupleWritable. It adds a
> var-int indicating size of field after each type code. This is a limitation
> of the writable system. We do not know the size of each field until fully
> desalinizing it.
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