lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Paul Elschot <paul.elsc...@xs4all.nl>
Subject Re: Possible IndexInput optimization
Date Sun, 29 Mar 2009 15:31:14 GMT
On Sunday 29 March 2009 13:47:59 Earwin Burrfoot wrote:
> > Earwin,
> > I did not experiment lately, but I'd like to add a general compressed
> > integer array to the basic types in an index, that would be compressed
> > on writing and decompressed on reading.
> > A first attempt is at LUCENE-1410, and one of the choices I had there
> > was whether or not to use NIO buffer methods on the index side.
> > I started there using these NIO buffer methods, but it seems that
> > the explicit byte arrays you're using here could be a good alternative.
> > I think my question boils down to whether or not these NIO buffers will
> > (in the end) get in the way of similar low level optimizations
> > you'd like to see applied here.
> > Regards,
> >
> > Paul Elschot
> In my case I have to switch to MMap/Buffers, Java behaves ugly with
> 8Gb heaps. 

Do you mean that because garbage collection does not perform well
on these larger heaps, one should avoid to create arrays to have heaps
of that size, and rather use (direct) MMap/Buffers?

> I'm thinking of trying to use Short/Int/LongBuffers that
> wrap my initial ByteBuffer.

So far I have used an IntBuffer wrapping a ByteBuffer at LUCENE-1410.
In case arrays are better not created for data to be read from index,
I'll keep it that way, hoping that that doesn't run into backward
compatibility problems.

Regards,
Paul Elschot

> 
> -- 
> Kirill Zakharenko/Кирилл Захаренко (earwin@gmail.com)
> Home / Mobile: +7 (495) 683-567-4 / +7 (903) 5-888-423
> ICQ: 104465785
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: java-dev-unsubscribe@lucene.apache.org
> For additional commands, e-mail: java-dev-help@lucene.apache.org
> 
> 
> 
> 

Mime
View raw message