Re: Read consistency

Hi Arko, Never used that consistency level so far, but here is some information: http://docs.datastax.com/en/cassandra/2.0/cassandra/dml/dml_tunable_consistency_c.html Cassandra 2.0 uses the Paxos consensus protocol, which resembles 2-phase > commit, to support linearizable consistency. All opera

Re: Read consistency

On Tue, Mar 15, 2016 at 6:43 PM, Arko Provo Mukherjee < arkoprovomukher...@gmail.com> wrote: > I am designing a system where for a situation, I need to have SERIAL > consistency during writes. > Be sure to understand the implications of : https://issues.apache.org/jira/browse/CASSANDRA-9328 =Ro

Re: Read Consistency

On Tue, Jun 30, 2015 at 11:16 AM, Tyler Hobbs wrote: > > Correct, if you get a WriteTimeout error, you don't know if any replicas > have written the data or not. It's even possible that all replicas wrote > the data but didn't respond to the coordinator in time. I suspect most > users handle th

Re: Read Consistency

On Tue, Jun 30, 2015 at 12:27 PM, Anuj Wadehra wrote: > Agree Tyler. I think its our application problem. If client returns failed > write in spite of retries, application must have a rollback mechanism to > make sure old state is restored. Failed write may be because of the fact > that CL was no

Re: Read Consistency

Agree Tyler. I think its our application problem. If client returns failed write in spite of retries, application must have a rollback mechanism to make sure old state is restored. Failed write may be because of the fact that CL was not met even though one node successfully wrote.Cassandra wont

Re: Read Consistency

Anuj Wadehra wrote: > Sorry for typo in your name Owen !! > > Anuj > > Sent from Yahoo Mail on Android > <https://overview.mail.yahoo.com/mobile/?.src=Android> > -- > *From*:"Anuj Wadehra" > *Date*:Sun, 28 Jun, 2015 at 11:1

Re: Read Consistency

Sorry for typo in your name Owen !! Anuj Sent from Yahoo Mail on Android From:"Anuj Wadehra" Date:Sun, 28 Jun, 2015 at 11:11 pm Subject:Re: Read Consistency Agree Owem !! Response in both scenarios would depend on the 2 replicas chosen for meeting QUORUM. But, the intent is to get the tricky

Re: Read Consistency

Agree Owem !! Response in both scenarios would depend on the 2 replicas chosen for meeting QUORUM. But, the intent is to get the tricky part of scenario 1 answered i.e. when 2 nodes selected are one with and one without data.  As per my understanding of Read Path and documentation https://wiki.a

Re: Read Consistency

ehra" > > *Date*:Wed, 24 Jun, 2015 at 12:15 am > *Subject*:Re: Read Consistency > > M more confused...Different responses. .Anyone who can explain with 100% > surity ? > > Thanks > Anuj > > > Sent from Yahoo Mail on Android > <https://overview.mail.yahoo.c

Re: Read Consistency

Thanks..So all of us agree that in scenario 1, data would be returned and that was my initial understanding.. Anuj Sent from Yahoo Mail on Android From:"Anuj Wadehra" Date:Wed, 24 Jun, 2015 at 12:15 am Subject:Re: Read Consistency M more confused...Different responses. .Anyone who can ex

Re: Read Consistency

M more confused...Different responses. .Anyone who can explain with 100% surity ? Thanks Anuj Sent from Yahoo Mail on Android From:"arun sirimalla" Date:Wed, 24 Jun, 2015 at 12:00 am Subject:Re: Read Consistency Thanks good to know that. On Tue, Jun 23, 2015 at 11:27 AM, Philip Thompson

Re: Read Consistency

t;> Why would it fail and with what Thrift error? What if the data didnt >>>> exist on any of the nodes..query wont fail if doesnt find data.. >>>> >>>> Not convinced.. >>>> >>>> Sent from Yahoo Mail on Android >>>> <https://overv

Re: Read Consistency

Not convinced.. >>> >>> Sent from Yahoo Mail on Android >>> <https://overview.mail.yahoo.com/mobile/?.src=Android> >>> -- >>> *From*:"arun sirimalla" >>> *Date*:Tue, 23 Jun, 2015 at 11:39 pm >>> *Subject*:Re: Read Consistency >

Re: Read Consistency

ail if doesnt find data.. >> >> Not convinced.. >> >> Sent from Yahoo Mail on Android >> <https://overview.mail.yahoo.com/mobile/?.src=Android> >> ------ >> *From*:"arun sirimalla" >> *Date*:Tue, 23 Jun, 2015 at 11:

Re: Read Consistency

t find data.. >> >> Not convinced.. >> >> Sent from Yahoo Mail on Android >> <https://overview.mail.yahoo.com/mobile/?.src=Android> >> -- >> *From*:"arun sirimalla" >> *Date*:Tue, 23 Jun, 2015 at 11:39 pm &

Re: Read Consistency

if the data didnt exist > on any of the nodes..query wont fail if doesnt find data.. > > Not convinced.. > > Sent from Yahoo Mail on Android > <https://overview.mail.yahoo.com/mobile/?.src=Android> > -- > *From*:"arun sirimalla" &

Re: Read Consistency

Date*:Tue, 23 Jun, 2015 at 11:39 pm > *Subject*:Re: Read Consistency > > Scenario 1: Read query is fired for a key, data is found on one node and > not found on other two nodes who are responsible for the token > corresponding to key. > > You read query will fail, as it expects to

Re: Read Consistency

Why would it fail and with what Thrift error? What if the data didnt exist on any of the nodes..query wont fail if doesnt find data.. Not convinced.. Sent from Yahoo Mail on Android From:"arun sirimalla" Date:Tue, 23 Jun, 2015 at 11:39 pm Subject:Re: Read Consistency Scenario 1: Read query i

Re: Read Consistency

Scenario 1: Read query is fired for a key, data is found on one node and not found on other two nodes who are responsible for the token corresponding to key. You read query will fail, as it expects to receive data from 2 nodes with RF=3 Scenario 2: Read query is fired and all 3 replicas have dif

Re: read consistency and clock drift and ntp

Here some links related do C* and clock synchronization: http://www.datastax.com/dev/blog/why-cassandra-doesnt-need-vector-clocks http://ria101.wordpress.com/2011/02/08/cassandra-the-importance-of-system-clocks-avoiding-oom-and-how-to-escape-oom-meltdown/ 2013/9/11 Jimmy Lin > hi, > I have