Known issues in parallel

From Gerris

Revision as of 08:36, 10 March 2012 Zaleski (Talk | contribs) (initial revision) ← Previous diff		Revision as of 08:41, 10 March 2012 Zaleski (Talk | contribs) Next diff →
Line 1:		Line 1:
	== A two-box simulation gives different results with one or two pids ==		== A two-box simulation gives different results with one or two pids ==
-	We run a simplified version of the [http://gerris.dalembert.upmc.fr/gerris/examples/examples|/cylinder.html#htoc3Benard Von-Karman test case]. The modified simulation file is	+	[[user:zaleski|We]] run a simplified version of the [http://gerris.dalembert.upmc.fr/gerris/examples/examples|/cylinder.html#htoc3Benard Von-Karman test case]. The modified simulation file is
	<pre>		<pre>
Line 23:		Line 23:
	1 2 right		1 2 right
	</pre>		</pre>
		+
		+	We use the following version of Gerris
		+
		+	<pre>
		+	%gerris2D -V
		+	gerris: using 2D libgfs version 1.3.2 (120229-075733 + local changes)
		+	compiled with flags: -DBSD_SOURCE -D_DARWIN_C_SOURCE
		+	MPI: yes
		+	pkg-config: yes
		+	m4: yes
		+	</pre>
		+
		+	Here is the result of running without mpi on MacOS 10.7.3 on a MacBook Pro with a four-core intel i7 system

---

Revision as of 08:41, 10 March 2012

A two-box simulation gives different results with one or two pids

We run a simplified version of the Von-Karman test case. The modified simulation file is

2 1  GfsSimulation GfsBox GfsGEdge {} {
  Time { iend = 0 }
  Refine 6
  Solid (x*x + y*y - 0.0625*0.0625)
  OutputTime { istep = 1 } stderr
  OutputProjectionStats { istep = 1 } stderr
  OutputSimulation { start = 0.1 step = 0.1} simulation.gfs {
      variables = U,V,P
  }
}

GfsBox { id=1 pid=0
  left = Boundary {
       BcDirichlet U 1
  }
}
GfsBox { id=2 pid=1 right = BoundaryOutflow }
1 2 right

We use the following version of Gerris

%gerris2D -V
gerris: using 2D libgfs version 1.3.2 (120229-075733 + local changes)
  compiled with flags:  -DBSD_SOURCE -D_DARWIN_C_SOURCE
  MPI:          yes
  pkg-config:   yes
  m4:           yes

Here is the result of running without mpi on MacOS 10.7.3 on a MacBook Pro with a four-core intel i7 system