[ 
https://issues.apache.org/jira/browse/SOLR-17725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18042376#comment-18042376
 ] 

ASF subversion and git services commented on SOLR-17725:
--------------------------------------------------------

Commit ae8b468b1043c6e50a387756d9ceab8d1fe974c7 in solr's branch 
refs/heads/branch_10_0 from Rahul Goswami
[ https://gitbox.apache.org/repos/asf?p=solr.git;h=ae8b468b104 ]

SOLR-17725: Add MergePolicy to block older segments from participating in 
merges (#3883)

Helps with Solr upgrades in conjunction with re-indexing.
New: LatestVersionFilterMergePolicy

---------

Co-authored-by: Rahul Goswami <[email protected]>

> Automatically upgrade Solr indexes without needing to reindex from source
> -------------------------------------------------------------------------
>
>                 Key: SOLR-17725
>                 URL: https://issues.apache.org/jira/browse/SOLR-17725
>             Project: Solr
>          Issue Type: Improvement
>            Reporter: Rahul Goswami
>            Priority: Major
>              Labels: pull-request-available
>         Attachments: High Level Design.png
>
>          Time Spent: 2h 10m
>  Remaining Estimate: 0h
>
> Today upgrading from Solr version X to X+2 requires complete reingestion of 
> data from source. This comes from Lucene's constraint which only guarantees 
> index compatibility between the version the index was created in and the 
> immediate next version. 
> This reindexing usually comes with added downtime and/or cost. Especially in 
> case of deployments which are in customer environments and not completely in 
> control of the vendor, this proposition of having to completely reindex the 
> data can become a hard sell.
> I, on behalf of my employer, Commvault, have developed a way which achieves 
> this reindexing in-place on the same index. Also, the process automatically 
> keeps "upgrading" the indexes over multiple subsequent Solr upgrades without 
> needing manual intervention. 
> It comes with the following limitations:
> i) All _source_ fields need to be either stored=true or docValues=true. Any 
> copyField destination fields can be stored=false of course, just that the 
> source fields (or more precisely, the source fields you care about 
> preserving) should be either stored or docValues true. 
> ii) The datatype of an existing field in schema.xml shouldn't change upon 
> Solr upgrade. Introducing new fields is fine. 
> For indexes where this limitation is not a problem (it wasn't for us!), the 
> tool can reindex in-place on the same core with zero downtime and 
> legitimately "upgrade" the index. This can remove a lot of operational 
> headaches, especially in environments with hundreds/thousands of very large 
> indexes.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to