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Re: CASSANDRA-13241 lower default chunk_length_in_kb




> On Oct 12, 2018, at 6:46 AM, Pavel Yaskevich <xedin@xxxxxxxxxx> wrote:
> 
>> On Thu, Oct 11, 2018 at 4:31 PM Ben Bromhead <ben@xxxxxxxxxxxxxxx> wrote:
>> 
>> This is something that's bugged me for ages, tbh the performance gain for
>> most use cases far outweighs the increase in memory usage and I would even
>> be in favor of changing the default now, optimizing the storage cost later
>> (if it's found to be worth it).
>> 
>> For some anecdotal evidence:
>> 4kb is usually what we end setting it to, 16kb feels more reasonable given
>> the memory impact, but what would be the point if practically, most folks
>> set it to 4kb anyway?
>> 
>> Note that chunk_length will largely be dependent on your read sizes, but 4k
>> is the floor for most physical devices in terms of ones block size.
>> 
> 
> It might be worth while to investigate how splitting chunk size into data,
> index and compaction sizes would affect performance.
> 

Data chunk and index chunk are already different (though one is table level and one is per instance), but I’m not parsing the compaction comment? 
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