diff --git a/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/AbstractIndexAstChecker.java b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/AbstractIndexAstChecker.java
index 7a1ce49f73b..7b0c5b1145b 100644
--- a/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/AbstractIndexAstChecker.java
+++ b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/AbstractIndexAstChecker.java
@@ -15,14 +15,10 @@ import org.eclipse.cdt.codan.core.cxx.Activator;
 import org.eclipse.cdt.codan.core.model.AbstractChecker;
 import org.eclipse.cdt.codan.core.model.IProblemLocation;
 import org.eclipse.cdt.codan.core.model.IRunnableInEditorChecker;
-import org.eclipse.cdt.core.CCorePlugin;
 import org.eclipse.cdt.core.dom.ast.IASTFileLocation;
 import org.eclipse.cdt.core.dom.ast.IASTNode;
 import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
 import org.eclipse.cdt.core.index.IIndex;
-import org.eclipse.cdt.core.model.CoreModel;
-import org.eclipse.cdt.core.model.ICElement;
-import org.eclipse.cdt.core.model.ITranslationUnit;
 import org.eclipse.cdt.internal.core.resources.ResourceLookup;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IProject;
@@ -44,24 +40,19 @@ public abstract class AbstractIndexAstChecker extends AbstractChecker implements
 	protected IFile getFile() {
 		return file;
 	}
+
 	protected IProject getProject() {
-		return file==null?null:file.getProject();
+		return file == null ? null : file.getProject();
 	}
 
 	void processFile(IFile file) throws CoreException, InterruptedException {
-		// create translation unit and access index
-		ICElement model = CoreModel.getDefault().create(file);
-		if (!(model instanceof ITranslationUnit))
-			return; // not a C/C++ file
-		ITranslationUnit tu = (ITranslationUnit) model;
-		IIndex index = CCorePlugin.getIndexManager().getIndex(tu.getCProject());
+		IASTTranslationUnit ast = CxxModelsCache.getInstance().getAst(file);
+		if (ast == null)
+			return;
 		// lock the index for read access
+		IIndex index = CxxModelsCache.getInstance().getIndex(file);
 		index.acquireReadLock();
 		try {
-			// create index based ast
-			IASTTranslationUnit ast = tu.getAST(index,
-					ITranslationUnit.AST_SKIP_INDEXED_HEADERS);
-			if (ast==null) return;//
 			// traverse the ast using the visitor pattern.
 			this.file = file;
 			processAst(ast);
@@ -87,21 +78,21 @@ public abstract class AbstractIndexAstChecker extends AbstractChecker implements
 	}
 
 	@SuppressWarnings("restriction")
-	public void reportProblem(String id, IASTNode astNode, Object...  args) {
+	public void reportProblem(String id, IASTNode astNode, Object... args) {
 		IASTFileLocation astLocation = astNode.getFileLocation();
 		IPath location = new Path(astLocation.getFileName());
-		IFile astFile = ResourceLookup.selectFileForLocation(location, getProject());
+		IFile astFile = ResourceLookup.selectFileForLocation(location,
+				getProject());
 		if (astFile == null) {
 			astFile = file;
 		}
 		if (astFile == null) {
-			Activator.log("Cannot resolve location: "+location); //$NON-NLS-1$
+			Activator.log("Cannot resolve location: " + location); //$NON-NLS-1$
 			return;
 		}
 		IProblemLocation loc;
 		int line = astLocation.getStartingLineNumber();
-		if (line == astLocation
-				.getEndingLineNumber())
+		if (line == astLocation.getEndingLineNumber())
 			loc = getRuntime().getProblemLocationFactory()
 					.createProblemLocation(
 							astFile,
@@ -110,8 +101,7 @@ public abstract class AbstractIndexAstChecker extends AbstractChecker implements
 									+ astLocation.getNodeLength(), line);
 		else
 			loc = getRuntime().getProblemLocationFactory()
-					.createProblemLocation(astFile,
-							line);
+					.createProblemLocation(astFile, line);
 		getProblemReporter().reportProblem(id, loc, args);
 	}
 
@@ -128,11 +118,12 @@ public abstract class AbstractIndexAstChecker extends AbstractChecker implements
 	 * (java.lang.Object)
 	 */
 	@SuppressWarnings("restriction")
-	public void processModel(Object model) {
+	public synchronized void processModel(Object model) {
 		if (model instanceof IASTTranslationUnit) {
 			IASTTranslationUnit ast = (IASTTranslationUnit) model;
 			IPath location = new Path(ast.getFilePath());
-			IFile astFile = ResourceLookup.selectFileForLocation(location, getProject());
+			IFile astFile = ResourceLookup.selectFileForLocation(location,
+					getProject());
 			file = astFile;
 			processAst(ast);
 		}
diff --git a/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/CxxModelsCache.java b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/CxxModelsCache.java
new file mode 100644
index 00000000000..9ab45f7435a
--- /dev/null
+++ b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/model/CxxModelsCache.java
@@ -0,0 +1,72 @@
+/*******************************************************************************
+ * Copyright (c) 2009 Alena Laskavaia 
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Alena Laskavaia  - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.codan.core.cxx.model;
+
+import org.eclipse.cdt.core.CCorePlugin;
+import org.eclipse.cdt.core.dom.ast.IASTTranslationUnit;
+import org.eclipse.cdt.core.index.IIndex;
+import org.eclipse.cdt.core.model.CoreModel;
+import org.eclipse.cdt.core.model.ICElement;
+import org.eclipse.cdt.core.model.ITranslationUnit;
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.runtime.CoreException;
+
+/**
+ * Cache data models for resource so checkers can share it
+ */
+public class CxxModelsCache {
+	private IFile file;
+	private IASTTranslationUnit ast;
+	private ITranslationUnit tu;
+	private IIndex index;
+
+	private static CxxModelsCache instance = new CxxModelsCache();
+
+	public static CxxModelsCache getInstance() {
+		return instance;
+	}
+
+	public synchronized IASTTranslationUnit getAst(IFile file)
+			throws CoreException, InterruptedException {
+		if (file.equals(this.file)) {
+			return ast;
+		}
+
+		// create translation unit and access index
+		ICElement celement = CoreModel.getDefault().create(file);
+		if (!(celement instanceof ITranslationUnit))
+			return null; // not a C/C++ file
+		this.file = file;
+		System.err.println("Making ast for "+file);
+		tu = (ITranslationUnit) celement;
+		index = CCorePlugin.getIndexManager().getIndex(tu.getCProject());
+		// lock the index for read access
+		index.acquireReadLock();
+		try {
+			// create index based ast
+			ast = tu.getAST(index, ITranslationUnit.AST_SKIP_INDEXED_HEADERS);
+			if (ast == null)
+				return null;//
+			return ast;
+		} finally {
+			index.releaseReadLock();
+		}
+	}
+
+	public synchronized IIndex getIndex(IFile file)
+			throws CoreException, InterruptedException {
+		if (file.equals(this.file)) {
+			return index;
+		}
+		getAst(file); // to init variables
+		return index;
+	}
+}
diff --git a/codan/org.eclipse.cdt.codan.core/src/org/eclipse/cdt/codan/internal/core/CodanBuilder.java b/codan/org.eclipse.cdt.codan.core/src/org/eclipse/cdt/codan/internal/core/CodanBuilder.java
index 7506bc4567c..1a94cedd8a6 100644
--- a/codan/org.eclipse.cdt.codan.core/src/org/eclipse/cdt/codan/internal/core/CodanBuilder.java
+++ b/codan/org.eclipse.cdt.codan.core/src/org/eclipse/cdt/codan/internal/core/CodanBuilder.java
@@ -115,6 +115,8 @@ public class CodanBuilder extends IncrementalProjectBuilder implements
 		CheckersRegisry chegistry = CheckersRegisry.getInstance();
 		for (IChecker checker : chegistry) {
 			try {
+				if (monitor.isCanceled())
+					return;
 				if (chegistry.isCheckerEnabled(checker, resource)
 						&& checker.enabledInContext(resource)) {
 					checker.processResource(resource);