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From Jamie <>
Subject Re: search performance
Date Mon, 02 Jun 2014 13:08:00 GMT
I assume you meant 1000 documents. Yes, the page size is in fact 
configurable. However, it only obtains the page size * 3. It preloads 
the following and previous page too. The point is, it only obtains the 
documents that are needed.

On 2014/06/02, 3:03 PM, Tincu Gabriel wrote:
> My bad, It's using the RamDirectory as a cache and a delegate directory
> that you pass in the constructor to do the disk operations, limiting the
> use of the RamDirectory to files that fit a certain size. So i guess the
> underlying Directory implementation will be whatever you choose it to be.
> I'd still try using a MMapDirectory and see if that improves performance.
> Also, regarding the pagination, you said you're retrieving 1000 documents
> at a time. Does that mean that if a query matches 10000 documents you want
> all of them retrieved ?
> On Mon, Jun 2, 2014 at 12:51 PM, Jamie <> wrote:
>> I was under the impression that NRTCachingDirectory will instantiate an
>> MMapDirectory if a 64 bit platform is detected? Is this not the case?
>> On 2014/06/02, 2:09 PM, Tincu Gabriel wrote:
>>> MMapDirectory will do the job for you. RamDirectory has a big warning in
>>> the class description stating that the performance will get killed by an
>>> index larger than a few hundred MB, and NRTCachingDirectory is a wrapper
>>> for RamDirectory and suitable for low update rates. MMap will use the
>>> system RAM to cache as much of the index it can and only hit disk when the
>>> portion of the index you're trying to access isn't cached. I'd put my
>>> money
>>> on switching directory implementations and see what kind of performance
>>> gains that brings to the table.

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