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Date: Thu, 25 Apr 2013 08:54:03 -0400
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Subject: Has anyone tested Red Hat's Transparent Huge Pages with Accumulo?
From: David Medinets <david.medinets@gmail.com>
To: accumulo-dev <dev@accumulo.apache.org>
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>From http://goo.gl/k4UkQ:

Simply put, huge pages are blocks of memory that come in 2MB and 1GB sizes.
The page tables used by the 2MB pages are suitable for managing multiple
gigabytes of memory, whereas the page tables of 1GB pages are best for
scaling to terabytes of memory.

>From http://bk.kolics.net/?p=68:

The maximum search rate with no large pages resulted in 10-15% lower rate
than with transparent huge pages enabled.

I looked at one of my Red Hat servers:

$ cat /sys/kernel/mm/transparent_hugepage/enabled
[always] never

So we might get some performance improvement if this option was enabled.
But if someone has already tried, I'd love to know the results.

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