java - The API which tells the cassandra cluster is overloaded or not -


i have java application uses datastax drive communicate cassandra. have requirement query cassandra if not overloaded. @ application level (not manually ) how know cassandra overloaded or not? datastax provide such api ?? looking method boolean iscassoverloded() ..kindly me in this.

thanks answers .. trying more specific stat's more interested in checking 'live size' , 'key count' of column family. know nodetool --host cfstats gives both value in java using datastax how both? if datastax not provide such api there rest api exposed cassandra give information?

at application level (not manually ) how know cassandra overloaded or not? datastax provide such api ?? looking method boolean iscassoverloded()

simple answer, such magic api not exist. providing such api on driver level require:

  1. being able define healthy node compared overloaded node
  2. being able collect health status of any node in cluster in real time
  3. being able propagate health status nodes in cluster without hammering local network

point 1. pretty hard achieve because node health may depends on various hardware factor (cpu usage, disk i/o, ...) , getting infos require installing system agents on machines

point 2. , 3. implemented gossip protocol gossip tells wether node up/down , level of suspicion, not if node overloaded or idle

to notified of status of node (up or down), can register host status listerner on driver: http://docs.datastax.com/en/drivers/java/2.1/com/datastax/driver/core/host.statelistener.html


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