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Noble Paul commented on SOLR-725: --------------------------------- bq.It's like a rename, but doesn't remove the source. Is RENAME really used ? is it useful? bq.That's not atomic... requests that come in between can fail. Point taken . bq.you already can have these problems with swap SWAP is a special case . It always ensure that the original name is not gone. The url will remain valid . SWAP is very useful if you wish to test the core before replacing it with an existing core. Because Solr is mostly used as a web-app , I feel the url is an important identifier for an asset (till it is removed). It is OK to make it available by another name (I can always have a fixed url with the name , other names can come and go ). But, the asset remaining alive and the url is invalid makes me think of it as a not so desirable feature. bq.I dont see how aliases are different than the name itself; My proposal wanted to treat them as different. Name is fixed , and aliases are like symlinks. And the core does not even have to be aware of it. I am just -0 on the hardlink approach. I just made my points against it > CoreContainer/CoreDescriptor/SolrCore cleansing > ----------------------------------------------- > > Key: SOLR-725 > URL: https://issues.apache.org/jira/browse/SOLR-725 > Project: Solr > Issue Type: Improvement > Affects Versions: 1.3 > Reporter: Henri Biestro > Attachments: solr-725.patch, solr-725.patch, solr-725.patch > > > These 3 classes and the name vs alias handling are somewhat confusing. > The recent SOLR-647 & SOLR-716 have created a bit of a flux. > This issue attemps to clarify the model and the list of operations. > h3. CoreDescriptor: describes the parameters of a SolrCore > h4. Definitions > * has one name > ** The CoreDescriptor name may represent multiple aliases; in that > case, first alias is the SolrCore name > * has one instance directory location > * has one config & schema name > h4. Operations > The class is only a parameter passing facility > h3. SolrCore: manages a Lucene index > h4. Definitions > * has one unique *name* (in the CoreContainer) > ** the *name* is used in JMX to identify the core > * has one current set of *aliases* > ** the name is the first alias > h4. Name & alias operations > * *get name/aliases*: obvious > * *alias*: adds an alias to this SolrCore > * *unalias*: removes an alias from this SolrCore > * *name*: sets the SolrCore name > ** potentially impacts JMX registration > * *rename*: picks a new name from the SolrCore aliases > ** triggered when alias name is already in use > h3. CoreContainer: manages all relations between cores & descriptors > h4. Definitions > * has a set of aliases (each of them pointing to one core) > ** ensure alias uniqueness. > h4. SolrCore instance operations > * *load*: makes a SolrCore available for requests > ** creates a SolrCore > ** registers all SolrCore aliases in the aliases set > ** (load = create + register) > * *unload*: removes a core idenitified by one of its aliases > ** stops handling the Lucene index > ** all SolrCore aliases are removed > * *reload*: recreate the core identified by one of its aliases > * *create*: create a core from a CoreDescriptor > ** readies up the Lucene index > * *register*: registers all aliases of a SolrCore > > h4. SolrCore alias operations > * *swap*: swaps 2 aliases > ** method: swap > * *alias*: creates 1 alias for a core, potentially unaliasing a > previously used alias > ** The SolrCore name being an alias, this operation might trigger > a SolrCore rename > * *unalias*: removes 1 alias for a core > ** The SolrCore name being an alias, this operation might trigger > a SolrCore rename > * *rename*: renames a core > h3. CoreAdminHandler: handles CoreContainer operations > * *load*/*create*: CoreContainer load > * *unload*: CoreContainer unload > * *reload*: CoreContainer reload > * *swap*: CoreContainer swap > * *alias*: CoreContainer alias > * *unalias*: CoreContainer unalias > * *rename*: CoreContainer rename > * *persist*: CoreContainer persist, writes the solr.xml > * *stauts*: returns the status of all/one SolrCore -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.