Hi Clint, The values of SSTables, Write Latency and Read Latency will be reset on node start/restart and after running the cfhistograms command itself.
The values of Row Size and Column Count are calculated at startup and then re-evaluated during compaction. Mark On 16 November 2014 17:12, Clint Kelly <clint.ke...@gmail.com> wrote: > Hi all, > > Over what time range does "nodetool cfhistograms" operate? > > I am using Cassandra 2.0.8.39. > > I am trying to debug some very high 95th and 99th percentile read > latencies in an application that I'm working on. > > I tried running nodetool cfhistograms to get a flavor for the > distribution of read latencies and also to see how many SSTables our > reads are using, and I saw different results yesterday versus this > morning, so I assume the time window is fairly tight (like an hour or > so). I vaguely recall Aaron Morton talking about this during the > training course I took at Cassandra Summit, but I cannot find my notes > and I think the behavior of the tool with regard to time windows > changed from version to version. > > Thanks! > > -Clint >
