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From Manu Zhang <owenzhang1...@gmail.com>
Subject Re:
Date Thu, 27 Sep 2012 02:32:51 GMT
I still don't see it in jconsole. BTW, how long would you expect to cost to
read a column family of 150000 rows if it fits into row cache entirely? It
takes me around 7s now. My experiment is done on a single node.

On Thu, Sep 27, 2012 at 6:00 AM, aaron morton <aaron@thelastpickle.com>wrote:

> Set the caching strategy for the CF to be ROWS_ONLY.
>
> Cheers
>
> -----------------
> Aaron Morton
> Freelance Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 26/09/2012, at 2:18 PM, Manu Zhang <owenzhang1990@gmail.com> 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 <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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