Re: fio-1.34.1, what we are doing with it and some patches we use.

[Jens Axboe <jens.axboe@oracle.com>]

On Fri, Oct 30 2009, Glen Ogilvie wrote:
> Dear Jens Axboe and the FIO mailing list.
> 
> I have been working with Mike O'Sullivan, a senior lecturer at the
> University of Auckland, New Zealand. He has been adapting fio 1.34.1
> to work with iolog files and also to be able to read a "wait" command
> to allow the iolog file to specify a wait (in millisecs) before the
> next io. Mike's not completely confident that his changes are correct
> in the overall fio picture, but they are working with the iolog files
> we are using. What we did:
> 
> 1) We incorporated wait into iolog file reading; 2) We made some
> modifications so that read_iolog worked.
> 
> We have attached a patch for fio-1.34.1.tar.bz2 along with some
> demonstration fio config files and iolog files.
> 
> We are doing this so we can use an open source SPC-1 emulator to
> generate SPC-1 like workloads and then run them in fio.
> 
> Hope some of this work is useful.   Feed back is welcome, we are not
> experts in FIO and SPC-1, so this may have problems.

Interesting! I think the patch you attached is reversed, you want to
diff old tree -> new tree. Otherwise the patch looks nice and simple,
one of the hunks look like a generic bug fix for leaking memory and
probably should be applied first as it isn't really part of this
"feature".

Another thing to keep in mind is the format of the iolog file. Did you
check whether the old versions just ignore the 'wait' line? If yes, we
can keep the format. Otherwise we probably need to bump it.

-- 
Jens Axboe