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From aaron morton <>
Subject Re:
Date Wed, 26 Sep 2012 22:00:49 GMT
Set the caching strategy for the CF to be ROWS_ONLY.


Aaron Morton
Freelance Developer

On 26/09/2012, at 2:18 PM, Manu Zhang <> wrote:

> The DEFAULT_CACHING_STRATEGY is Caching.KEYS_ONLY but even configuring row cache size
to be greater zero 
>  won't enable row cache. Why? 
> On Wed, Sep 26, 2012 at 9:44 AM, Manu Zhang <> wrote:
> I wonder now if "get_range_slices" call will ever look for data in row cache. I don't
see it in the codebase. Only the "get" call will check row cache?
> On Wed, Sep 26, 2012 at 12:11 AM, Charles Brophy <> wrote:
> 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 <> 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.

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