Yes, there isn't any place in the JMX with reads/second or writes/second, just CompletedTasks. I send this info to Graphite ( http://graphite.wikidot.com/) and use the "derivative" function to get reads/minute. Munin also does the trick (https://github.com/tcurdt/jmx2munin). But you can't do that with cassandra itself, you need somewhere to make the calculations (cacti is also a good match).
Hope that helps. There is some more information about monitoring this kind of things here: http://www.tomas.cat/blog/en/monitoring-cassandra-relevant-data-should-be-watched-and-how-send-it-graphite 2013/5/13 Hiller, Dean <dean.hil...@nrel.gov> > We running a pretty consistent load on our cluster and added a new node to > a 6 node cluster Friday(QA worked great, but production not so much). One > mistake that was made was starting up the new node, then disabling the > firewall :( which allowed nodes to discover it BEFORE the node bootstrapped > itself. We shutdown the node and booted him up and he bootstrapped himself > streaming all the data in. > > After that though, all the ndoes have really really high load numbers now. > We are trying to figure out what is going on still. > > Is there any way to get the number of reads/second and writes/second > through JMX or something? The only way I can see of on doing this is > manually calculating it by timing the read count and dividing by my manual > stop watches start/stop times(timerange). > > Also, while my load is load average: 20.31, 19.10, 19.72 , what does a > normal iostat look like? My iostat await time is 13.66 ms which I think is > kind of bad, but not that bad to cause a load of 20.31? > > Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz > avgqu-sz await svctm %util > sda 0.02 0.07 11.70 1.96 1353.67 702.88 150.58 > 0.19 13.66 3.61 4.93 > sdb 0.00 0.02 0.11 0.46 20.72 97.54 206.70 > 0.00 1.33 0.67 0.04 > > Thanks, > Dean > -- [image: Groupalia] <http://es.groupalia.com/> www.groupalia.com <http://es.groupalia.com/>Tomàs NúñezIT-SysprodTel. + 34 93 159 31 00 Fax. + 34 93 396 18 52Llull, 95-97, 2º planta, 08005 BarcelonaSkype: tomas.nunez.groupaliatomas.nu...@groupalia.com<nombre.apell...@groupalia.com>[image: Twitter] Twitter <http://twitter.com/#%21/groupaliaes> [image: Twitter] Facebook <https://www.facebook.com/GroupaliaEspana> [image: Twitter] Linkedin <http://www.linkedin.com/company/groupalia>
<<linkedin.png>>
<<facebook.png>>
<<groupalia.jpg>>
<<twitter.png>>
