flimzy commented on a change in pull request #252: Suggested edit to make clear what a quorum actually represents. URL: https://github.com/apache/couchdb-documentation/pull/252#discussion_r171891485
########## File path: src/cluster/theory.rst ########## @@ -34,10 +34,17 @@ thereby override the defaults in ``default.ini``. The number of copies of a document with the same revision that have to be read before CouchDB returns with a ``200`` is equal to a half of total copies of -the document plus one. It is the same for the number of nodes that need to -save a document before a write is returned with ``201``. If there are less -nodes than that number, then ``202`` is returned. Both read and write numbers -can be specified with a request as ``r`` and ``w`` parameters accordingly. +the document plus one *in the current partition*. That is, if there is a network Review comment: Ah, now I see what you're getting at. That is an important point. And the paragraph was already a bit confusing before your addition. Perhaps a rewrite of the entire section is in order. Example: > In clustered operation, a quorum must be reached before CouchDB returns a ``200`` for a fetch, or ``201`` for a write operation. A quorum is defined one plus half the number of copies. > For read operations, the maximum number of copies is the number of currently-accessible nodes, meaning that in the case of a failure or network partition, the effective number of copies may be lower. The number of read copies can be set with the ``r``parameter. > For write operations, the number of copies can be set using the ``w`` parameter. If fewer than this number of nodes is available, a ``202`` will be returned. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
