Yes, you should if average object size exceeds 4KB because otherwise Ignite 
will spend more time spreading and maintaining a single object across several 
pages. 

—
Denis

> On Nov 7, 2017, at 11:14 AM, Andrey Kornev <[email protected]> wrote:
> 
> Thanks Ivan! A follow-up question, if you don't mind. 
> 
> Should I consider changing the default 4K page size to 8K (or possibly to 
> 16K) if the average size of my cache objects is, say, 12K, with max size up 
> to 100K?
> 
> Thanks
> Andrey
> 
> From: Ivan Rakov <[email protected]>
> Sent: Tuesday, November 7, 2017 8:22 AM
> To: [email protected]
> Subject: Re: Data region's data page size
>  
> Hello Andrey,
> 
> Short answer: just keep default 4k page size, it will work fine unless you 
> have very specific hardware.
> 
> Too small page size causes write amplification on hardware level: 
> https://www.cactus-tech.com/resources/blog/details/write-amplification-as-seen-in-solid-state-drives
>  
> <https://www.cactus-tech.com/resources/blog/details/write-amplification-as-seen-in-solid-state-drives>
> On the other hand, too big page size causes write amplification on Ignite 
> level. Whole 16k page will be persisted if you have changed only few bytes.
> 
> You may also want to check our durable memory tuning guide for more 
> details:https://apacheignite.readme.io/docs/durable-memory-tuning 
> <https://apacheignite.readme.io/docs/durable-memory-tuning>
> Best Regards,
> Ivan Rakov
> 
> On 07.11.2017 1:28, Andrey Kornev wrote:
>> Hello,
>> 
>> What are the considerations for choosing the best data page size? It looks 
>> like there are only four possible values (1K, 4K, 8K and 16K) to choose 
>> from, and I don't immediately see why one would want to use anything other 
>> than 16K?
>> 
>> Is it because the value lookup within a page is linear and therefore, I want 
>> to keep the number of values that fit on a single page sufficiently low?
>> 
>> Please advise!
>> 
>> Thanks
>> Andrey

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