As part of debugging an IO generator, I've run across an odd set of results under RH 6.4 running on x64 hardware (validated on multiple systems):

-- The application uses async IO

-- The application reports 100 io/s, and 60% writes.

-- strace of the application reports 100 calls per second to io_submit() and io_getevents(), reflecting 100 AIO operations per second

-- 'dstat --aio' shows 100 ops per second

-- iostat reports 40 reads/sec, as expected, but 120 writes/second, twice as many as expected

Have you seen this behavior? Is it a known bug?

Thanks.

Jack

Duplicate post. Reported for closure.