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From Vick Khera <>
Subject Re: performance tuning - where does the slowness come from?
Date Thu, 06 May 2010 14:21:43 GMT
On Wed, May 5, 2010 at 8:08 PM, Kyusik Chung <> wrote:
> if the data from the sstables hasnt already been loaded into memory by mmap,
> load it into memory; if you're out of memory on the box, swap some of the
> old mmapped data out of memory

mmap() does not copy your data into memory; it maps your virtual
address space to the disk file, so you can treat the file as memory,
usually an array of bytes or structures.  or is mmap on java different
than that in C?

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