Re: A fio job that just waits?

[Erwan Velu <e.velu@criteo.com>]

Le 27/01/2022 à 00:08, Nick Neumann a écrit :
> Is there a clean way to create a fio job that just waits for a fixed
> time period? I'm fairly new to fio, and want a delay between two
> consecutive jobs. I use "wait_for" to serialize as needed, and
> expected "startdelay" to allow me to put the desired delay between the
> two. But it looks like the startdelay for a job begins when fio starts
> and not when the job referenced in a "wait_for" finishes.
>
> I can play games with a job with a very low bandwidth limit (e.g.
> 1B/s) and "runtime" and "time_based", but it feels hacky.
>
> Am I thinking about how to get a delay between two jobs wrong? Is
> there a better way? I realize I could just run fio multiple times with
> command line delays between the runs, but I'd like the results of the
> runs to share the same time basis and output/log files.

Nick,

I've been adding an exec engine in fio that could be used to do any kind 
of behavior.

There is an example where I wanted to perform explicit sleeps between 
jobs to cool down the server : 
https://github.com/axboe/fio/blob/master/examples/exec.fio

You may try something like that 
https://github.com/axboe/fio/tree/master/tools/fiograph can help you 
graphing how jobs are interlaced.

If you look at 
https://github.com/axboe/fio/blob/master/examples/exec.png, it gives a 
visual representation of the sleep action in this example.


That may help you,

Erwan,