BitmappedReachabilityChecker: Use only one bitmap for the whole check

The checker is creating a new bitmap per branch leading to excessive
memory consumption. For the reachability check one bitmap with the
reachability of all branches aggregated is enough.

Build the reachability bitmap with a filter. The filter itself uses it
to emit only commits not reached before and the caller to check what
targets have been reached already.

BitmapCalculator is not required anymore.

Change-Id: Ic5c62f77fe0f188913215b7eaa51d849a9aae6a5
Signed-off-by: Ivan Frade <ifrade@google.com>

1 files changed, 0 insertions, 181 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/BitmapCalculatorTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/BitmapCalculatorTest.java
deleted file mode 100644
index c5d4d4238d..0000000000
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/BitmapCalculatorTest.java
+++ /dev/null
@@ -1,181 +0,0 @@
-/*
- * Copyright (C) 2019, Google LLC.
- * and other copyright owners as documented in the project's IP log.
- *
- * This program and the accompanying materials are made available
- * under the terms of the Eclipse Distribution License v1.0 which
- * accompanies this distribution, is reproduced below, and is
- * available at http://www.eclipse.org/org/documents/edl-v10.php
- *
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or
- * without modification, are permitted provided that the following
- * conditions are met:
- *
- * - Redistributions of source code must retain the above copyright
- *   notice, this list of conditions and the following disclaimer.
- *
- * - Redistributions in binary form must reproduce the above
- *   copyright notice, this list of conditions and the following
- *   disclaimer in the documentation and/or other materials provided
- *   with the distribution.
- *
- * - Neither the name of the Eclipse Foundation, Inc. nor the
- *   names of its contributors may be used to endorse or promote
- *   products derived from this software without specific prior
- *   written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-package org.eclipse.jgit.revwalk;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
-import org.eclipse.jgit.internal.storage.file.FileRepository;
-import org.eclipse.jgit.internal.storage.file.GC;
-import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
-import org.eclipse.jgit.junit.TestRepository;
-import org.eclipse.jgit.lib.BitmapIndex.BitmapBuilder;
-import org.eclipse.jgit.lib.NullProgressMonitor;
-import org.eclipse.jgit.lib.ProgressMonitor;
-import org.junit.Before;
-import org.junit.Test;
-
-public class BitmapCalculatorTest extends LocalDiskRepositoryTestCase {
-	TestRepository<FileRepository> repo;
-
-	/** {@inheritDoc} */
-	@Override
-	@Before
-	public void setUp() throws Exception {
-		super.setUp();
-		FileRepository db = createWorkRepository();
-		repo = new TestRepository<>(db);
-	}
-
-	@Test
-	public void addOnlyCommits() throws Exception {
-		RevBlob abBlob = repo.blob("a_b_content");
-		RevCommit root = repo.commit().add("a/b", abBlob).create();
-		repo.update("refs/heads/master", root);
-
-		// GC creates bitmap index with ALL objects
-		GC gc = new GC(repo.getRepository());
-		gc.setAuto(false);
-		gc.gc();
-
-		// These objects are not in the bitmap index.
-		RevBlob acBlob = repo.blob("a_c_content");
-		RevCommit head = repo.commit().parent(root).add("a/c", acBlob).create();
-		repo.update("refs/heads/master", head);
-
-		BitmapCalculator bitmapWalker = new BitmapCalculator(repo.getRevWalk());
-		BitmapBuilder bitmap = bitmapWalker
-				.getBitmap(head, NullProgressMonitor.INSTANCE);
-
-		assertTrue(bitmap.contains(root.getId()));
-		assertTrue(bitmap.contains(root.getTree().getId()));
-		assertTrue(bitmap.contains(abBlob.getId()));
-
-		// BitmapCalculator added only the commit, no other objects.
-		assertTrue(bitmap.contains(head.getId()));
-		assertFalse(bitmap.contains(head.getTree().getId()));
-		assertFalse(bitmap.contains(acBlob.getId()));
-	}
-
-	@Test
-	public void walkUntilBitmap() throws Exception {
-		RevCommit root = repo.commit().create();
-		repo.update("refs/heads/master", root);
-
-		// GC creates bitmap index with ALL objects
-		GC gc = new GC(repo.getRepository());
-		gc.setAuto(false);
-		gc.gc();
-
-		// These objects are not in the bitmap index.
-		RevCommit commit1 = repo.commit(root);
-		RevCommit commit2 = repo.commit(commit1);
-		repo.update("refs/heads/master", commit2);
-
-		CounterProgressMonitor monitor = new CounterProgressMonitor();
-		BitmapCalculator bitmapWalker = new BitmapCalculator(repo.getRevWalk());
-		BitmapBuilder bitmap = bitmapWalker.getBitmap(commit2, monitor);
-
-		assertTrue(bitmap.contains(root));
-		assertTrue(bitmap.contains(commit1));
-		assertTrue(bitmap.contains(commit2));
-		assertEquals(2, monitor.getUpdates());
-	}
-
-	@Test
-	public void noNeedToWalk() throws Exception {
-		RevCommit root = repo.commit().create();
-		RevCommit commit1 = repo.commit(root);
-		RevCommit commit2 = repo.commit(commit1);
-		repo.update("refs/heads/master", commit2);
-
-		// GC creates bitmap index with ALL objects
-		GC gc = new GC(repo.getRepository());
-		gc.setAuto(false);
-		gc.gc();
-
-		CounterProgressMonitor monitor = new CounterProgressMonitor();
-		BitmapCalculator bitmapWalker = new BitmapCalculator(repo.getRevWalk());
-		BitmapBuilder bitmap = bitmapWalker.getBitmap(commit2, monitor);
-
-		assertTrue(bitmap.contains(root));
-		assertTrue(bitmap.contains(commit1));
-		assertTrue(bitmap.contains(commit2));
-		assertEquals(0, monitor.getUpdates());
-	}
-
-	private static class CounterProgressMonitor implements ProgressMonitor {
-
-		private int counter;
-
-		@Override
-		public void start(int totalTasks) {
-			// Nothing to do in tests
-		}
-
-		@Override
-		public void beginTask(String title, int totalWork) {
-			// Nothing to to in tests
-		}
-
-		@Override
-		public void update(int completed) {
-			counter += 1;
-		}
-
-		@Override
-		public void endTask() {
-			// Nothing to do in tests
-		}
-
-		@Override
-		public boolean isCancelled() {
-			return false;
-		}
-
-		int getUpdates() {
-			return counter;
-		}
-	}
-}
\ No newline at end of file