Fixed ProfilingGraph calculation integer overflows and added test class.

Complementary to fix proposed in PR #128 by @otteresk.

1 files changed, 108 insertions, 0 deletions

diff --git a/test/java/net/yacy/peers/graphics/ProfilingGraphTest.java b/test/java/net/yacy/peers/graphics/ProfilingGraphTest.java
new file mode 100644
index 000000000..318b469c0
--- /dev/null
+++ b/test/java/net/yacy/peers/graphics/ProfilingGraphTest.java
@@ -0,0 +1,108 @@
+// ProfilingGraphTest.java
+// Copyright 2017 by luccioman; https://github.com/luccioman
+//
+// This is a part of YaCy, a peer-to-peer based web search engine
+//
+// LICENSE
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+package net.yacy.peers.graphics;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+
+import net.yacy.cora.util.ConcurrentLog;
+import net.yacy.search.EventTracker;
+import net.yacy.visualization.RasterPlotter;
+
+/**
+ * Unit tests for the {@link ProfilingGraph} class
+ */
+public class ProfilingGraphTest {
+
+	/**
+	 * Generate a performance graph and write it to a temporary file for manual
+	 * viasual checking.<br/>
+	 * Note : it is not an automated JUnit test function as it is time dependant.
+	 *
+	 * @throws IOException
+	 *             when a read/write exception occurred
+	 * @throws InterruptedException
+	 *             when interrupted before termination
+	 */
+	public static void main(final String args[]) throws IOException, InterruptedException {
+		long time = System.currentTimeMillis();
+		final long beginTime = time;
+		long prevTime = time;
+
+		/* Feed the event tracker with test values */
+		final int steps = 100;
+
+		/* Ascending memory usage from 500MB to 16GB */
+		long bytes = 500L * 1024L * 1024L;
+		final long bytesStep = (16L * 1204L * 1204L * 1204L) / steps;
+
+		/* Descending words, from max integer value to zero.
+		 * (events values are stored as long, but currently the actual maximum possible value ford WORDCACHE is an Integer.MAX_VALUE) */
+		long words = Integer.MAX_VALUE;
+		final long wordsStep = words / steps;
+
+		for (int step = 0; step < steps; step++) {
+			if ((step % 30) == 0) {
+				/* Stable PPRM and peer ping values */
+				EventTracker.update(EventTracker.EClass.PPM, Long.valueOf(500), false);
+				EventTracker.update(EventTracker.EClass.PEERPING,
+						new ProfilingGraph.EventPing("localPeerName", "aaaa", true, 1536), false);
+			}
+			EventTracker.update(EventTracker.EClass.WORDCACHE, Long.valueOf(words), false);
+			EventTracker.update(EventTracker.EClass.MEMORY, Long.valueOf(bytes), false);
+			time = System.currentTimeMillis();
+			/* Ensure each test event is separated at least from 1ms */
+			while (time == prevTime) {
+				Thread.sleep(1);
+				time = System.currentTimeMillis();
+			}
+			prevTime = time;
+
+			bytes += bytesStep;
+			words -= wordsStep;
+		}
+
+		long timeRange = (time - beginTime) * 2;
+
+		/* Parameters likely to be encountered on the PerformanceGraph calling class */
+		final int indexSizeCache = 865749;
+		final int rwiCount = 512378;
+		final int rwiBufferCount = 6754;
+		final RasterPlotter graph = ProfilingGraph.performanceGraph(660, 240,
+				indexSizeCache + " URLS / " + rwiCount + " WORDS IN INDEX / " + rwiBufferCount + " WORDS IN CACHE",
+				(int) timeRange, TimeUnit.MILLISECONDS, true, true);
+
+		/* Now write the result to a temporary file for visual checking */
+		final File outputFile = new File(System.getProperty("java.io.tmpdir"), "testPerformanceGraph.png");
+		try (
+				/* Automatically closed by this try-with-resources statement */
+				final FileOutputStream fos = new FileOutputStream(outputFile);) {
+			fos.write(RasterPlotter.exportImage(graph.getImage(), "png").getBytes());
+			System.out.println("Performance graph writtent to file " + outputFile);
+		} finally {
+			ConcurrentLog.shutdown();
+		}
+	}
+
+}