Re: crashblk: a block device crash emulator.

[Josef Bacik]

On 01/15/2016 01:45 AM, Takashi HOSHINO wrote:
> Hi Andreas,
>
> On 2016/01/15 4:44, Andreas Dilger wrote:
> > On Jan 13, 2016, at 6:50 PM, Takashi HOSHINO
> > <hoshino@xxxxxxxxxxxxxxxxx> wrote:
> > > Hi all,
> > >
> > > I'm developing 'crashblk'.
> > > It is a memory block device driver to emulate crash, IO error,
> > > and various response time.
> >
> > Why not use/improve dm-flakey for this, rather than making yet another
> > device that does something similar?
>
> I did not know dm-flakey until your reply. Thank you.
>
> I read its documents and code a bit.
> The big purpose of two projects are the same, which is to test software
> on block devices with errors, but their functions are almost different.
>
> It may be nice idea to implement alternative implementation of crashblk
> on device-mapper version by someone.
> Currently I'm not familiar with device-mapper development, and I do not
> have any motivation with it.

There's also dm-log-writes which will log writes to an external journal 
to allow you to replay writes and verify the fs is consistent at all 
steps of operation.  Thanks,

Josef