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Submitted By: https://www.google.com/accounts ()
Assigned to: Nobody/Anonymous (nobody)
Summary: Block device - block size, Inaccurate Results
Under linux, dynamo opens physical device without O_DIRECT flag, resulting in higher performance due to device buffered i/o.
Example: Sector Size 512, Block Size 4096.
Access Specification: 512 Bytes Read.
Test will open the block device and perform 4096 reads opposed to 512, resulting in ~8x higher performance.
Fix: In function TargetDisk::Open (ln 1499 on iometer-1.1.0-rc1-src), add O_DIRECT to open flags.