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https://issues.apache.org/jira/browse/CASSANDRA-6890?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14026490#comment-14026490
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Joshua McKenzie commented on CASSANDRA-6890:
--------------------------------------------

That's a fair point - just pulling out the memory mapped file path is a pretty 
simple effort that could easily be integrated into CASSANDRA-5863.  For the 3.0 
release and Windows stability, we have it hard-coded in our DatabaseDescriptor 
to not allow memory-mapped file I/O on Windows so there's really no functional 
difference as far as platform stability on that front.

> Standardize on a single read path
> ---------------------------------
>
>                 Key: CASSANDRA-6890
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-6890
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Joshua McKenzie
>            Assignee: Joshua McKenzie
>              Labels: performance
>             Fix For: 3.0
>
>         Attachments: 6890_v1.txt, mmap_gc.jpg, mmap_jstat.txt, mmap_perf.txt, 
> nommap_gc.jpg, nommap_jstat.txt
>
>
> Since we actively unmap unreferenced SSTR's and also copy data out of those 
> readers on the read path, the current memory mapped i/o is a lot of 
> complexity for very little payoff.  Clean out the mmapp'ed i/o on the read 
> path.



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