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Dikang Gu commented on CASSANDRA-11432: --------------------------------------- [~iamaleksey], any ideas about this? Thanks! > Counter values become under-counted when running repair. > -------------------------------------------------------- > > Key: CASSANDRA-11432 > URL: https://issues.apache.org/jira/browse/CASSANDRA-11432 > Project: Cassandra > Issue Type: Bug > Reporter: Dikang Gu > Assignee: Aleksey Yeschenko > > We are experimenting Counters in Cassandra 2.2.5. Our setup is that we have 6 > nodes, across three different regions, and in each region, the replication > factor is 2. Basically, each nodes holds a full copy of the data. > We are writing to cluster with CL = 2, and reading with CL = 1. > When are doing 30k/s counter increment/decrement per node, and at the > meanwhile, we are double writing to our mysql tier, so that we can measure > the accuracy of C* counter, compared to mysql. > The experiment result was great at the beginning, the counter value in C* and > mysql are very close. The difference is less than 0.1%. > But when we start to run the repair on one node, the counter value in C* > become much less than the value in mysql, the difference becomes larger than > 1%. > My question is that is it a known problem that the counter value will become > under-counted if repair is running? Should we avoid running repair for > counter tables? > Thanks. -- This message was sent by Atlassian JIRA (v6.3.4#6332)