Work around issue #559 in training material.

docs/programmers/tutorials/workflows/grayscale_app.py

@@ -1,16 +1,24 @@
+import os
+from os.path import basename
+
 from gc3libs import Application
+from gc3libs.quantity import GB
+
 
 class GrayscaleApp(Application):
-  """Convert an image file to grayscale."""
-  def __init__(self, img):
-    inp = basename(img)
-    out = "gray-" + inp
-    Application.__init__(
-      self,
-      arguments=[
-        "convert", inp, "-colorspace", "gray", out],
-      inputs=[img],
-      outputs=[out],
-      output_dir="grayscale.d",
-      stdout="stdout.txt",
-      stderr="stderr.txt")
+    """Convert an image file to grayscale."""
+    def __init__(self, img):
+        inp = basename(img)
+        out = "gray-" + inp
+        Application.__init__(
+            self,
+            arguments=[
+                "convert", inp, "-colorspace", "gray", out],
+            inputs=[img],
+            outputs=[out],
+            output_dir="grayscale.d",
+            stdout="stdout.txt",
+            stderr="stderr.txt",
+            # this is needed to circumvent GC3Pie issue #559, see
+            # <https://github.com/uzh/gc3pie/issues/559>
+            requested_memory=1*GB)

docs/programmers/tutorials/workflows/solutions/ex2c.py

@@ -6,6 +6,7 @@
 
 from gc3libs import Application
 from gc3libs.cmdline import SessionBasedScript
+from gc3libs.quantity import GB
 
 
 if __name__ == '__main__':
@@ -42,4 +43,7 @@ def __init__(self, img):
             outputs=[out],
             output_dir="grayscale.d",
             stdout="stdout.txt",
-            stderr="stderr.txt")
+            stderr="stderr.txt",
+            # this is needed to circumvent GC3Pie issue #559, see
+            # <https://github.com/uzh/gc3pie/issues/559>
+            requested_memory=1*GB)