[
https://issues.apache.org/jira/browse/NUTCH-1113?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13907160#comment-13907160
]
Sebastian Nagel commented on NUTCH-1113:
----------------------------------------
Hi [~markus17], tried test data from NUTCH-1706 with the latest patch
(2014-01-22) applied:
{code}
# 4. merge segments
% bin/nutch mergesegs merged crawl/segments/20131115203640/ \
crawl/segments/20131115203847/ \
crawl/segments/20140217140849/
# 5. index merged segment
% bin/nutch index -Dplugin.includes="index-basic|indexer-dummy"
-Ddummy.path=index2014_merged.txt crawl/crawldb \
merged/* -deleteGone
# 6. diff indexes (cf. NUTCH-1706): all documents with status
fetch_not_modified in the latest of the merged segments are lost!
% diff index2013.txt index2014_merged.txt
9d8
< add http://nutch.apache.org/
26d24
< add http://tika.apache.org/
{code}
In addtion to fetch_retry, we also need to exclude fetch_notmodified from
merging.
> Merging segments causes URLs to vanish from crawldb/index?
> ----------------------------------------------------------
>
> Key: NUTCH-1113
> URL: https://issues.apache.org/jira/browse/NUTCH-1113
> Project: Nutch
> Issue Type: Bug
> Affects Versions: 1.3
> Reporter: Edward Drapkin
> Priority: Blocker
> Fix For: 1.9
>
> Attachments: NUTCH-1113-junit.patch, NUTCH-1113-junit.patch,
> NUTCH-1113-junit.patch, NUTCH-1113-junit.patch, NUTCH-1113-junit.patch,
> NUTCH-1113-junit.patch, NUTCH-1113-trunk.patch, merged_segment_output.txt,
> unmerged_segment_output.txt
>
>
> When I run Nutch, I use the following steps:
> nutch inject crawldb/ url.txt
> repeated 3 times:
> nutch generate crawldb/ segments/ -normalize
> nutch fetch `ls -d segments/* | tail -1`
> nutch parse `ls -d segments/* | tail -1`
> nutch update crawldb `ls -d segments/* | tail -1`
> nutch mergesegs merged/ -dir segments/
> nutch invertlinks linkdb/ -dir merged/
> nutch index index/ crawldb/ linkdb/ -dir merged/ (I forward ported the lucene
> indexing code from Nutch 1.1).
> When I crawl with merging segments, I lose about 20% of the URLs that wind up
> in the index vs. when I crawl without merging the segments. Somehow the
> segment merger causes me to lose ~20% of my crawl database!
--
This message was sent by Atlassian JIRA
(v6.1.5#6160)
