Hello, This metric is available indeed:
Most of the metrics available are documented here: http://cassandra.apache.org/doc/latest/operating/metrics.html For client requests (coordinator perspective latency): http://cassandra.apache.org/doc/latest/operating/metrics.html#client-request-metrics For local requests (per table/host latency, locally, no network communication included): http://cassandra.apache.org/doc/latest/operating/metrics.html#table-metrics LatencySpecial type that tracks latency (in microseconds) with a Timer plus > a Counter that tracks the total latency accrued since starting. The > former is useful if you track the change in total latency since the last > check. Each metric name of this type will have ‘Latency’ and ‘TotalLatency’ > appended to it. You need 'Latency', not 'TotalLatency'. I would guess that's the issue because latencies are available for as far as I remember (including C*2.0, 1.2 for sure :)). Also, be aware that quite a few things changed in the metric structure between C* 2.1 and C*2.2 (and C*3.0 is similar to C*2.2). Examples of changes: - ColumnFamily --> Table - 99percentile --> p99 - 1MinuteRate --> m1_rate - metric name before KS and Table names and some other changes of this kind. - ^ aggregations / aliases and indexes changed because of this ^ - breaking most of the charts (in my case at least). - ‘.value’ is not appended to the metric name anymore for gauges, nothing instead. For example (Grafana / Graphite): From ```aliasByNode(averageSeriesWithWildcards(cassandra.$env.$dc.$host.org.apache.cassandra.metrics.ColumnFamily.$ks.$table.ReadLatency.95percentile, 2, 3), 1, 7, 8, 9)``` to ```aliasByNode(averageSeriesWithWildcards(cassandra.$env.$dc.$host.org.apache.cassandra.metrics.Table.ReadLatency.$ks.$table.p95, 2, 3), 1, 8, 9, 10)``` Another tip, is to use ccm locally (https://github.com/riptano/ccm) for example and 'jconsole $cassandra_pid'. I use this -->jconsole $(ccm node1 show | grep pid | awk -F= '{print $2}') Once you're in, you can explore available mbeans and find the metrics available in 'org.apache.cassandra.[...]'. It's not ideal as you search 'manually' but it allowed me to find some metrics in the past or fix issues from the doc above. Out of curiosity, may I ask what backend you used for your monitoring? C*heers, ----------------------- Alain Rodriguez - al...@thelastpickle.com France / Spain The Last Pickle - Apache Cassandra Consulting http://www.thelastpickle.com Le mer. 29 mai 2019 à 15:32, shalom sagges <shalomsag...@gmail.com> a écrit : > Hi All, > > I'm creating a dashboard that should collect read/write latency metrics on > C* 3.x. > In older versions (e.g. 2.0) I used to divide the total read latency in > microseconds with the read count. > > Is there a metric attribute that shows read/write latency without the need > to do the math, such as in nodetool tablestats "Local read latency" output? > I saw there's a Mean attribute in org.apache.cassandra.metrics.ReadLatency > but I'm not sure this is the right one. > > I'd really appreciate your help on this one. > Thanks! > > >
