Fix CI (#465)

h2/src/test/org/h2/test/unit/TestFileSystem.java

@@ -815,6 +815,7 @@ public class TestFileSystem extends TestBase {
         final int size = getSize(10, 50);
         f.write(ByteBuffer.allocate(size * 64 *  1024));
         Random random = new Random(1);
+        System.gc();
         Task task = new Task() {
             @Override
             public void call() throws Exception {
@@ -864,6 +865,7 @@ public class TestFileSystem extends TestBase {
             ra.close();
             file.delete();
             FileUtils.delete(s);
+            System.gc();
         }
     }
 

h2/src/tools/org/h2/build/Build.java

@@ -931,6 +931,7 @@ public class Build extends BuildBase {
             ret = execJava(args(
                     "-ea",
                     "-Xmx128m",
+                    "-XX:MaxDirectMemorySize=2g",
                     "-cp", cp,
                     "org.h2.test.TestAll", "fast"));
         } else {