There are settings in cassandra.yaml that will _gradually_ reduce the available cache to zero if you are under constant memory pressure:
# Set to 1.0 to disable. <snip> reduce_cache_sizes_at: * reduce_cache_capacity_to: * My experience is that the cache size will not return to the configured size until a service restart if you leave this enabled. The text of this setting is not explicit about the long-term cache shrinkage, so it's easy to think that it will restore the cache to its configured size after the pressures have subsided. It won't. Charles On Tue, Sep 25, 2012 at 8:14 AM, Manu Zhang <owenzhang1...@gmail.com> wrote: > I've enabled row cache and set its capacity to 10MB but when I check its > size in jconsole it's always 0. Isn't it that a row will be written to row > cache if it isn't there when I read the row? I've bulk loaded the data into > disk so row cache is crucial to the performance.