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From Thibaut Britz <>
Subject Question about consitency level & data propagation & eventually consistent
Date Wed, 10 Nov 2010 14:54:41 GMT

Assuming I'm reading and writing with consitency level 1 (one), read repair
turned off, I have a few questions about data propagation.
Data is being stored at consistency level 3.

I'm not interested in the deletes. I can live with older data (or data that
has been deleted and will reappear), but I need to know how long it will
take until the data will be available at the other nodes, since I have
turned read repair off.

1) If all nodes are up:
 - Will all writes eventually reach all nodes (of the 3 nodes)?
 - What will be the maximal time until the last write reaches the last node
(of the 3 nodes)? (e.g. Assume one of the node is doing compactation at that

2) If one or two nodes are down
- As I understood it, one node will buffer the writes for the remaining
- If the nodes go up again: When will these writes be propagated, at
compactation?, what will be the maximal time until the writes reach the 2
nodes? Will these writes be propagated at all?

In case of 2:

The best way would then be to run nodetool repair after the two nodes will
be available again. Is there a way to make the node not accept any
connections during that time until it is finished repairing? (eg throw the


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