RAM Directory / querying Performance issue

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RAM Directory / querying Performance issue

zzzzz shalev
I've rewritten the RAM DIR to supprt 64 bit (still havent had time to add this to lucene, hopefully in the coming months when i have a free second)
   
  My question:
   
  i have a machine with 4 GB RAM
   
  i have a 3GB index file,
   
  i successfully load the 3GB index into memory,
   
  the first few queries run with normal response time,
   
  but very quickly response time becomes unbearably slow (webloading with 1 con user),
   
  how are queries expanded in memory when run (how much memory do they use up)?
   
  could this be an issue of the queries themselves talking up large chunks of RAM?
   
   
   
   
   

               
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Re: RAM Directory / querying Performance issue

Doug Cutting
Is this markedly faster than using an MMapDirectory?  Copying all this
data into the Java heap (as RAMDirectory does) puts a tremendous burden
on the garbage collector.  MMapDirectory should be nearly as fast, but
keeps the index out of the Java heap.

Doug

zzzzz shalev wrote:

> I've rewritten the RAM DIR to supprt 64 bit (still havent had time to add this to lucene, hopefully in the coming months when i have a free second)
>    
>   My question:
>    
>   i have a machine with 4 GB RAM
>    
>   i have a 3GB index file,
>    
>   i successfully load the 3GB index into memory,
>    
>   the first few queries run with normal response time,
>    
>   but very quickly response time becomes unbearably slow (webloading with 1 con user),
>    
>   how are queries expanded in memory when run (how much memory do they use up)?
>    
>   could this be an issue of the queries themselves talking up large chunks of RAM?
>    
>    
>    
>    
>    
>
>
> ---------------------------------
> Blab-away for as little as 1¢/min. Make  PC-to-Phone Calls using Yahoo! Messenger with Voice.

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