as of 1.0 (CASSANDRA-2034) hints are generated for nodes that timeout.
On Thu, Oct 11, 2012 at 3:55 AM, Watanabe Maki <watanabe.m...@gmail.com> wrote: > Even if HH works fine, HH will not be created until the failure detector > marks the node is dead. > HH will not be created for partially timeouted mutation request ( but meets > CL ) also... In my understanding... > > > On 2012/10/11, at 5:55, Rob Coli <rc...@palominodb.com> wrote: > >> On Tue, Oct 9, 2012 at 12:56 PM, Oleg Dulin <oleg.du...@gmail.com> wrote: >>> My understanding is that the repair has to happen within gc_grace period. >>> [ snip ] >>> So the question is, is this still needed ? Do we even need to run nodetool >>> repair ? >> >> If Hinted Handoff works in your version of Cassandra, and that version >> is > 1.0, you "should" not need to repair if no node has crashed or >> been down for longer than max_hint_window_in_ms. This is because after >> 1.0, any failed write to a remote replica results in a hint, so any >> DELETE should eventually be fully replicated. >> >> However hinted handoff is meaningfully broken between 1.1.0 and 1.1.6 >> (unreleased) so you cannot rely on the above heuristic for >> consistency. In these versions, you have to repair (or read repair >> 100% of keys) once every GCGraceSeconds to prevent the possibility of >> zombie data. If it were possible to repair on a per-columnfamily >> basis, you could get a significant win by only repairing >> columnfamilies which take DELETE traffic. >> >> https://issues.apache.org/jira/browse/CASSANDRA-4772 >> >> =Rob >> >> -- >> =Robert Coli >> AIM>ALK - rc...@palominodb.com >> YAHOO - rcoli.palominob >> SKYPE - rcoli_palominodb
