[PATCH] xfstests: add execution of a custom command to fsstress (-x and -X options)

[Jan Schmidt]

On 21.03.2013 20:50, Dave Chinner wrote:
> On Thu, Mar 21, 2013 at 11:59:45AM +0100, Jan Schmidt wrote:
>> From: Jan Schmidt <list.btrfs at jan-o-sch.net>
>>
>> This patch adds execution of a custom command in the middle of all fsstress
>> operations. Its intended use is the creation of snapshots in the middle of a
>> test run.
> 
> Why do you need fsstress to do this? Why can't you just run fsstress
> in the background and run a loop creating periodic snapshots in the
> control script?

Because I want reproducible results. Same random seed should result in
the very same snapshots being created.

> Also, did you intend that every process creates a snapshot? i.e. it
> looks lik eif you run a 1000 processes, they'll all run a snapshot
> operation at X operations? i.e. this will generate nproc * X
> snapshots in a single run. This doesn't seem very wise to me....

Agreed, I haven't thought of running more than one process. For the sake
of reproducibility, I wouldn't want multiple processes for my test case
either.

I'm not sure if there are other applications than snapshot creation for
such a feature, so I cannot argue whether to have each process execute
such a command or not.

Thanks,
-Jan