Re: Rapidly running systemtap causing hangs or oops

["Richard W.M. Jones" <rjones@redhat.com>]

On Thu, Jun 23, 2011 at 09:15:50AM -0700, Josh Stone wrote:
> On 06/23/2011 12:51 AM, Richard W.M. Jones wrote:
> > Unfortunately for the real program I'm writing, I really do need a way
> > to box stap around each test.  The problem I was having before was
> > that there was quite a long delay between my test running and stap
> > probes firing (or at least, seeing stap output).  I need the stap
> > output from one test to be clearly distinct from the stap output from
> > the next test.  If there was a way to run the test and then say to
> > stap "now flush all your output" before running the next test, then
> > that would be acceptable.
> > 
> > I thought about using the process ID, but ideally my tests will all
> > run as the same pid.
> 
> How about marking it with some other event that always and only happens
> at the beginning or end of your test loop?  e.g. take a mount:
> 
>   probe syscall.mount {
>     printf("Starting to mount %s on %s\n", source, target)
>   }

Something like this could work, but timestamps seem to be working
rather well now.

Rich.

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