[ https://issues.apache.org/jira/browse/LUCENE-8264?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16447257#comment-16447257 ]
Shawn Heisey commented on LUCENE-8264: -------------------------------------- On the dev list, [~yriveiro] replied to this issue. His indexes are up to 15 terabytes. (yowza!) Reindexing from scratch on an index that big is something you can't just decide to do one day. I really like the idea of rewriting all segments without merging them. The way that IndexUpgrader currently works can cause the LUCENE-7976 problems. > Allow an option to rewrite all segments > --------------------------------------- > > Key: LUCENE-8264 > URL: https://issues.apache.org/jira/browse/LUCENE-8264 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Erick Erickson > Assignee: Erick Erickson > Priority: Major > > For the background, see SOLR-12259. > There are several use-cases that would be much easier, especially during > upgrades, if we could specify that all segments get rewritten. > One example: Upgrading 5x->6x->7x. When segments are merged, they're > rewritten into the current format. However, there's no guarantee that a > particular segment _ever_ gets merged so the 6x-7x upgrade won't necessarily > be successful. > How many merge policies support this is an open question. I propose to start > with TMP and raise other JIRAs as necessary for other merge policies. > So far the usual response has been "re-index from scratch", but that's > increasingly difficult as systems get larger. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org