On 5/26/23 11:38, Travis Downs wrote:
> I guess I understand when fio "stops" when using 1 file per job: after
> `io_size` IOs,
> which is usually the same as `size` if `io_size` has not been
> specified explicitly.
>
> When size == io_size, this means that all blocks of the files are
> written exactly once
> with linear or random writes, except if norandmap=1, in which case
> some blocks will
> likely be written 0 times and others 2 or more times.
>
> How does this work for nrfiles > 1 and linear writes (rw=write) and
> file_service_type
> set to one of the random ones? For the non-uniform distributions some
> files will be
> written at a higher rate than others: does the write pointer just loop
> when it gets to
> the end of the file? So io_size writes will still be done, but some
> files will not be
> completely written while others may be written more than once?
>
> Travis
Fio's behavior in this situation is not explicitly spelled out in the
documentation.
For a job with a single file, fio will just start over again and write
the file multiple times when io_size > filesize. I would expect the same
to happen when nrfiles > 1.
Try a run with --debug=io,file and let us know!
Vincent
