Re: Off-heap row cache and mmapped sstables

[Rob Coli]

On 4/12/12, Omid Aladini <omidalad...@gmail.com> wrote:
> Cassandra issues an mlockall [1] before mmap-ing sstables to prevent
> the kernel from paging out heap space in favor of memory-mapped
> sstables. I was wondering, what happens to the off-heap row cache
> (saved or unsaved)? Is it possible that the kernel pages out off-heap
> row cache in favor of resident mmap-ed sstable pages?

For what it's worth, I find this conjecture plausible given my
understanding of the Cassandra ticket which resulted in the use of
JNA+mlockall. I'd love to hear an opinion from someone from the
project with more in-depth knowledge. :)

=Rob

-- 
=Robert Coli
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