Re: local read from coordinator

2020-11-11 Thread Alex Ott
Jeff, I was talking about driver -> coordinator communication, not from where data will be read On Wed, Nov 11, 2020 at 3:24 PM Jeff Jirsa wrote: > > This isn’t necessarily true and cassandra has no coordinator-only > consistency level to force this behavior > > (The snitch is going to pick the

Re: local read from coordinator

2020-11-11 Thread Jeff Jirsa
What you describe is true for writes but not reads. The read only gets sent to enough nodes to meet the consistency level, unless/until one of two things happen: - You trigger probabilistic read repair, in which case it's sent to all nodes (or all nodes in a DC), or - One of the chosen replicas

RE: local read from coordinator

2020-11-11 Thread Durity, Sean R
Doesn’t the read get sent to all nodes that own the data in parallel (from the coordinator)? And the first one that is able to respond wins (for LOCAL_ONE). That was my understanding. Sean Durity From: Jeff Jirsa Sent: Wednesday, November 11, 2020 9:24 AM To: user@cassandra.apache.org

Re: local read from coordinator

2020-11-11 Thread Jeff Jirsa
This isn’t necessarily true and cassandra has no coordinator-only consistency level to force this behavior (The snitch is going to pick the best option for local_one reads and any compactions or latency deviations from load will make it likely that another replica is chosen in practice) >

Re: Re: local read from coordinator

2020-11-11 Thread Alex Ott
if you force routing key, then the replica that owns the data will be selected as coordinator On Wed, Nov 11, 2020 at 12:35 PM onmstester onmstester wrote: > Thanx, > > But i'm OK with coordinator part, actually i was looking for kind of read > CL to force to read from the coordinator only with

Fwd: Re: local read from coordinator

2020-11-11 Thread onmstester onmstester
Thanx, But i'm OK with coordinator part, actually i was looking for kind of read CL to force to read from the coordinator only with no other connections to other nodes! Sent using https://www.zoho.com/mail/ Forwarded message From: Alex Ott To: "user" Date: