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Date: Sat, 18 Jun 2011 00:59:49 +0000 (UTC)
From: "Tom White (JIRA)" <jira@apache.org>
To: common-issues@hadoop.apache.org
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Subject: [jira] [Commented] (HADOOP-7206) Integrate Snappy compression
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    [ https://issues.apache.org/jira/browse/HADOOP-7206?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13051423#comment-13051423 ] 

Tom White commented on HADOOP-7206:
-----------------------------------

I noticed that the compression overhead in this patch is {{(bufferSize >> 3) + 128 + 3}} which is less than the maximum possible blowup that Snappy allows for (http://code.google.com/p/snappy/source/browse/trunk/snappy.cc#55). Should this be changed to {{bufferSize / 6 + 32}}?

> Integrate Snappy compression
> ----------------------------
>
>                 Key: HADOOP-7206
>                 URL: https://issues.apache.org/jira/browse/HADOOP-7206
>             Project: Hadoop Common
>          Issue Type: New Feature
>    Affects Versions: 0.21.0
>            Reporter: Eli Collins
>            Assignee: issei yoshida
>         Attachments: HADOOP-7206-002.patch, HADOOP-7206.patch, v2-HADOOP-7206-snappy-codec-using-snappy-java.txt, v3-HADOOP-7206-snappy-codec-using-snappy-java.txt, v4-HADOOP-7206-snappy-codec-using-snappy-java.txt
>
>
> Google release Zippy as an open source (APLv2) project called Snappy (http://code.google.com/p/snappy). This tracks integrating it into Hadoop.
> {quote}
> Snappy is a compression/decompression library. It does not aim for maximum compression, or compatibility with any other compression library; instead, it aims for very high speeds and reasonable compression. For instance, compared to the fastest mode of zlib, Snappy is an order of magnitude faster for most inputs, but the resulting compressed files are anywhere from 20% to 100% bigger. On a single core of a Core i7 processor in 64-bit mode, Snappy compresses at about 250 MB/sec or more and decompresses at about 500 MB/sec or more.
> {quote}

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