Re: no unlink file before write testing

On Tue, 2008-04-15 at 09:21 +0200, Jens Axboe wrote:
> On Tue, Apr 15 2008, Zhang, Yanmin wrote:
> >
> > On Mon, 2008-04-14 at 12:37 +0200, Jens Axboe wrote:
> > > On Mon, Apr 14 2008, Jens Axboe wrote:
> > > > On Tue, Apr 08 2008, Zhang, Yanmin wrote:
> > > > > Jens,
> > > > >
> > > > > As for write testing, fio chooses to unlink the files before testing.
> > > > > I run the testing on many big files, so the file preparation spends
> > > > > lots of time. Is it possible to add a new parameter, such like
> > > > > nounlinkwrite, to ask fio not to unlink files before testing? Its default
> > > > > value could be false.
> > > > >
> > > > > Current parameter overwrite always recreates the files.
> > > >
> > > > How about we just change that instead? If the file exists and is big
> > > > enough, there's no point in having 'overwrite' recreate the file.
> > >
> > > That seems to be how overwrite currently behaves (and, anything else
> > > would have surprised me).
> > >
> > > Can you come up with a concrete example that doesn't behave as expected?
> > You are right. originally, I was misled by function extend_file. After double-checking
> > it, I find caller setup_files has a checking before setting flag FIO_FILE_EXTEND.
> >
> > How about change below statement in HOWTO from:
> >
> > overwrite=bool If writing to a file, setup the file first and do overwrites.
> >
> > to:
> >
> > ???overwrite=bool If writing to a file and extending the file when setup, overwrites the
> > whole file.
>
> I changed it to:
>
> overwrite=bool If true, writes to a file will always overwrite existing
> data. If the file doesn't already exist, it will be
> created before the write phase begins. If the file exists
> and is large enough for the specified write phase, nothing
> will be done.
It's very clear now. Thanks.
Received on Tue Apr 15 2008 - 10:48:02 CEST