[ 
https://issues.apache.org/jira/browse/NUTCH-2455?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16272716#comment-16272716
 ] 

Semyon Semyonov commented on NUTCH-2455:
----------------------------------------

[~wastl-nagel]
What about this step read HostDatums together with CrawlDatums (cf. 
MultipleInputFormat, depends on NUTCH-2375) as input of the select step? 
Is not it simpler to read the HostDb in each mapper separately?

> Speed up the merging of HostDb entries for variable fetch delay
> ---------------------------------------------------------------
>
>                 Key: NUTCH-2455
>                 URL: https://issues.apache.org/jira/browse/NUTCH-2455
>             Project: Nutch
>          Issue Type: Improvement
>          Components: generator
>    Affects Versions: 1.13
>            Reporter: Markus Jelsma
>         Attachments: NUTCH-2455.patch
>
>
> Citing Sebastian at NUTCH-2420:
> ??The correct solution would be to use <host,score> pairs as keys in the 
> Selector job, with a partitioner and secondary sorting so that all keys with 
> same host end up in the same call of the reducer. If values can also hold a 
> HostDb entry and the sort comparator guarantees that the HostDb entry 
> (entries if partitioned by domain or IP) comes in front of all CrawlDb 
> entries. But that would be a substantial improvement...??



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

Reply via email to