What is the difference between accepting a value and committing a value?
On Wed, Feb 1, 2017 at 4:25 AM, Kant Kodali <k...@peernova.com> wrote: > Hi, > > Thanks for the response. I finished watching this video but I still got > few questions. > > 1) The speaker seems to suggest that there are different consistency > levels being used in different phases of paxos protocol. If so, what is > right consistency level to set on these phases? > > 2) Right now, we just set consistency level as QUORUM at the global level > and I dont think we ever change it so in this case what would be the > consistency levels being used in different phases. > > 3) The fact that one should think about reading before the commit phase or > after the commit phase (but not any other phase) sounds like there is > something special about commit phase and what is that? when I set the > QUORUM level consistency at global level Does the commit phase happen right > after accept phase or no? or irrespective of the consistency level when > does the commit phase happen anyway? and what happens during the commit > phase? > > > Thanks, > kant > > > On Wed, Feb 1, 2017 at 3:30 AM, Alain RODRIGUEZ <arodr...@gmail.com> > wrote: > >> Hi, >> >> I believe that this talk from Christopher Batey at the Cassandra Summit >> 2016 might answer most of your questions around LWT: >> https://www.youtube.com/watch?v=wcxQM3ZN20c >> >> He explains a lot of stuff including consistency considerations. My >> understanding is that the quorum read can only see the data written using >> LWT after the commit phase. A SERIAL Read would see it (video, around >> 23:40). >> >> Here are the slides as well: http://fr.slideshare.net >> /DataStax/light-weight-transactions-under-stress-christopher >> -batey-the-last-pickle-cassandra-summit-2016 >> >> Let us know if you still have questions after watching this (about 35 >> minutes). >> >> C*heers, >> ----------------------- >> Alain Rodriguez - @arodream - al...@thelastpickle.com >> France >> >> The Last Pickle - Apache Cassandra Consulting >> http://www.thelastpickle.com >> >> 2017-02-01 10:57 GMT+01:00 Kant Kodali <k...@peernova.com>: >> >>> When you initiate a LWT(write) and do a QUORUM read is there a chance >>> that one might not see the LWT write ? If so, can someone explain a bit >>> more? >>> >>> Thanks! >>> >> >> >
