[
https://issues.apache.org/jira/browse/SOLR-3816?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13486012#comment-13486012
]
Nagendra Nagarajayya commented on SOLR-3816:
--------------------------------------------
Lucene/Solr search and commit architecture is designed to work off a
“point-in-time snapshots” of the index. Any add/update/delete needs a commit to
be visible to searches (or atleast a soft-commit). soft-commit re-opens the
SolrIndexSearcher object and can be a performance limitation if the
soft-commits happen more than one per second, see
blog:http://searchhub.org/dev/2011/09/07/realtime-get/. Realtime NRT makes
available a near realtime view of the index. So any changes made to the index
is immediately visible. Performance is not a limitation as it does not close
the SolrIndexSearcher object as with soft-commit.
Realtime NRT is also different from realtime-get which is a simple lookup by id
and needs the transaction log to be enabled. realtime-get does not have search
capability. Realtime NRT allows full search, so you could search by id, text,
location, etc. using boolean, dismax, faceting, range queries ie. no change to
existing functionality. No new request handlers to be defined in
solrconfig.xml. So all of your existing queries work as it is with no changes,
except that the results returned are in near real time. Realtime NRT also does
not need the transaction update log needed by realtime-get. So you can turn
this off for improved performance. autoCommit freq can also be increased to an
hour from the default of 15 secs for improved performance (remember commits can
slow down your update performance)
More info about Realtime NRT and a integrated download of Solr 4.0 with
Realtime NRT is available here:
http://solr-ra.tgels.org/realtime-nrt.jsp
(Attached a patch for Solr 4.0 release branch)
> Need a more granular nrt system that is close to a realtime system.
> -------------------------------------------------------------------
>
> Key: SOLR-3816
> URL: https://issues.apache.org/jira/browse/SOLR-3816
> Project: Solr
> Issue Type: Improvement
> Components: clients - java, replication (java), search,
> SearchComponents - other, SolrCloud, update
> Affects Versions: 4.0
> Reporter: Nagendra Nagarajayya
> Labels: nrt, realtime, replication, search, solrcloud, update
> Attachments: solr-3816-realtime_nrt.patch
>
>
> Need a more granular NRT system that is close to a realtime system. A
> realtime system should be able to reflect changes to the index as and when
> docs are added/updated to the index. soft-commit offers NRT and is more
> realtime friendly than hard commit but is limited by the dependency on the
> SolrIndexSearcher being closed and reopened and offers a coarse granular NRT.
> Closing and reopening of the SolrIndexSearcher may impact performance also.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: dev-h...@lucene.apache.org
