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From Manu Zhang <owenzhang1...@gmail.com>
Subject Re:
Date Wed, 26 Sep 2012 02:18:42 GMT
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 <owenzhang1990@gmail.com> 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 <cbrophy@zulily.com>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 <owenzhang1990@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.
>>
>>
>>
>

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