Sorry to intrude in this thread, but my intention is to get a clarity on
read_repair_chance.
Our reads doesn't need near real time data, so all our reads use CL.ONE. In
this case, how read repair happens in the replicas? what should be the
ideal value of read_repair_chance in this case?
how often
In this case, how read repair happens in the replicas?
By default 90% of the reads will only read from 1 replica, and 10% will read
from all. However the client request will *only* wait for one replica to return
a value. And it has to be the replica that was asked to return the full data,
not
Hi,
I am trying to understand the read path in Cassandra. I've read Cassandra's
documentation and it seems that the read path is like this:
- Client contacts with a proxy node which performs the operation over
certain object
- Proxy node sends requests to every replica of that object
- Replica
You're missing the correct definition of read_repair_chance.
When you do a read at CL.ALL, all replicas are wait upon and the results
from all those replicas are compared. From that, we can extract which nodes
are not up to date, i.e. which ones can be read repair. And if some node
need to be
a, ok. Now I understand where the data came from. When using CL.ALL
read_repair always repairs inconsistent data.
Thanks a lot, Sylvain.
Carlos Pérez Miguel
2013/1/17 Sylvain Lebresne sylv...@datastax.com
You're missing the correct definition of read_repair_chance.
When you do a read
Hi there,
I am sorry to get into this thread with more questions but isn't the
gossip protocol in charge of making the read_repair automatically
anytime a new node comes into the ring? I mean if a node is down, then
we get that node up and running again, wouldn't it be synchronized
automatically?
I mean if a node is down, then
we get that node up and running again, wouldn't it be synchronized
automatically?
It will, thanks to hinted handoff (not gossip, gossip only handle the ring
topology and a bunch of metadata, it doesn't deal with data synchronization
at all). But hinted handoff
Thanks for the explanation Sylvain!
2013/1/16 Sylvain Lebresne sylv...@datastax.com:
I mean if a node is down, then
we get that node up and running again, wouldn't it be synchronized
automatically?
It will, thanks to hinted handoff (not gossip, gossip only handle the ring
topology and a
