the testing branch of the IO-500 scripts now supports stonewalling for
mdtest and ior, reducing the burden of users to define the appropriate
data size and metadata objects.
The creation phases of the benchmarks will start a wear-out phase
after (by default) 300s.
That means after 300s, the current number of iterations is exchanged
-- all processes must reach this number of iterations => thus, it
simulates the block-synchronous behaviour that have stragglers.
IMPORTANT: it may happen that certain processes are significantly
faster than others, then, of course, one has to wait longer than 300s.
Still, it reduces the burden to parameterize the benchmark and
accidentally wait for hours instead of minutes.
The version has been tested it on 64 nodes by me and George tested it at Kaust.
If you want to give it a shot, use the branch:
The behaviour is controlled by a new variable:
For testing, you may want to set it to, e.g., 1 ;-)
Once this is effective, we can simplify the scripts furthermore...
Thanks & Best,
Dr. Julian Kunkel
Lecturer, Department of Computer Science
+44 (0) 118 378 8218