Lucene Index size v/s memory

[Shakti Purohit <sh...@persistent.co.in>]

We are required to find out how much percentage/portion of lucene index needs to be in memory for acceptable search response times. The index size we have is around 100 GB while the available memory is 24 GB. Since we do not have the option of loading whole of the index in memory we wanted to know what minimum part of lucene index be loaded in memory so that response time is not affected.
Does the index consist of any files or hierarchy such that loading only this information in memory and not whole of the index would suffice for faster response time. 

The other question I have is how many queries per second lucene can support? We are interested in finding out throughput of the system.

Thanks in advance.
Shakti
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Re: Lucene Index size v/s memory

[Sean Owen <sr...@gmail.com>]

I think you maybe meant to send to java-user@lucene.apache.org?

On Tue, Dec 22, 2009 at 3:58 PM, Shakti Purohit
<sh...@persistent.co.in> wrote:
> We are required to find out how much percentage/portion of lucene index needs to be in memory for acceptable search response times. The index size we have is around 100 GB while the available memory is 24 GB. Since we do not have the option of loading whole of the index in memory we wanted to know what minimum part of lucene index be loaded in memory so that response time is not affected.
> Does the index consist of any files or hierarchy such that loading only this information in memory and not whole of the index would suffice for faster response time.
>
> The other question I have is how many queries per second lucene can support? We are interested in finding out throughput of the system.
>