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From Jeffrey Kesselman <jef...@gmail.com>
Subject Re: faster ByteBuffer comparison
Date Sat, 02 Jul 2011 16:47:46 GMT
I'd fetch it all at once into a single byte array and try Arrays.equals()

On Sat, Jul 2, 2011 at 12:45 PM, Jeffrey Kesselman <jeffpk@gmail.com> wrote:

> GetLong has to get it a byte at a time still to support endianess.
>
> Id have to think about it, but what you really want is to get it all
> into a byte array and then process it in  64bits. AIR there are some
> new array recasting things in Java 5+.  Ill need to go look at them
> more closely...
>
> On Fri, Jul 1, 2011 at 5:42 PM, Yang <teddyyyy123@gmail.com> wrote:
> > I can see from profiling that a lot of the time in both reading and
> writing
> > are spend on ByteBuffer compare on the column names (for long rows with
> many
> > columns)
> > I looked at the ByteBufferUtil.unsignedCompareByteBuffer() , it's
> basically
> > the same structure as standard JVM ByteBuffer.compare()
> > looping over each byte doing a ByteBuffer.get()
> > is there a faster (probably hardware-based) compare ? I tried doing 8
> bytes
> > at a time by doing getLong() and it actually seems slower
> > thanks
> > Yang
>
>
>
> --
> It's always darkest just before you are eaten by a grue.
>



-- 
It's always darkest just before you are eaten by a grue.

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