Re: [Qemu-devel] Help needed: test-qht-par hangs on Travis

["Emilio G. Cota" <cota@braap.org>]

On Mon, Dec 10, 2018 at 15:47:15 -0200, Eduardo Habkost wrote:
> On Sun, Dec 09, 2018 at 05:27:38PM -0500, Emilio G. Cota wrote:
> > On Fri, Dec 07, 2018 at 18:41:07 -0200, Eduardo Habkost wrote:
> > > I've noticed QEMU Travis builds are failing recently, and they
> > > seem to happen only on the --enable-gprof jobs.  I have enabled
> > > V=1 and noticed that the jobs are hanging inside test-qht-par.
> > > 
> > > Example here (look for "/qht/parallel/2threads-0%updates-1s"):
> > > 
> > > https://travis-ci.org/ehabkost/qemu-hacks/jobs/465081311
> > > 
> > > Does anybody have any idea why?
> > 
> > So if I read that output correctly, it seems that the second
> > test in qht-par never completes.
> > 
> > Enabling gprof and gcov (as in that build) should just lower
> > the throughput of the benchmark (test-qht-par invokes qht-bench),
> [...]
> 
> Unrelated question: is there a specific reason why test-qht-par
> is written in C using gtest, instead of being just a shell script
> that runs qht-bench?

I didn't know how to integrate a shell script with
gtester, so I went with a C program.

There's a possibility that the use of system(3) here is
what's causing the problem. Can you try running the following
branch on travis?
  https://github.com/cota/qemu/tree/test-qht-par
I moved most of qht-bench into qht-bench.inc.c, so that
both qht-bench.c and test-qht-par.c can use it. This
gets rid of the use of system(3) in test-qht-par.c.

Thanks,

		Emilio