[GitHub] sagelywizard opened a new pull request #477: Add LRU for view groups

[gi...@git.apache.org]

sagelywizard opened a new pull request #477: Add LRU for view groups
URL: https://github.com/apache/couchdb/pull/477
 
 
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   ## Overview
   
   This PR changes how CouchDB manages view indexes. Specifically, it 1) adds an LRU cache to couch_index_server for view groups 2) causes idle view groups to close if more than a configurable soft maximum number of indexes are open and 3) adds additional bookkeeping for couch_index_server to track if a view index is eligible for closing. The PR also has a few other changes in CouchDB for bits of code which assume view groups are never closed.
   
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        what problem it solves or how it makes things better. -->
   
   ## Testing recommendations
   
   This is primarily a performance improvement and shouldn't affect the API. This PR includes eunit tests, which can be run with `make check`.
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   ## JIRA issue number
   
   COUCHDB-3377
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   ## Related Pull Requests
   
   None
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   ## Checklist
   
   - [ ] Code is written and works correctly;
   - [ ] Changes are covered by tests;
   - [ ] Documentation reflects the changes;
   - [ ] I will not forget to update [rebar.config.script](https://github.com/apache/couchdb/blob/master/rebar.config.script)
         with the correct commit hash once this PR get merged.
   
 
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