Index: lucene/src/test-framework/org/apache/lucene/util/LuceneTestCase.java
===================================================================
--- lucene/src/test-framework/org/apache/lucene/util/LuceneTestCase.java	(revision 1177807)
+++ lucene/src/test-framework/org/apache/lucene/util/LuceneTestCase.java	(working copy)
@@ -303,6 +303,32 @@
     swapCodec(new PulsingCodec(), cp);
     cp.setDefaultFieldCodec(savedDefaultCodec);
   }
+  
+  // Support for @UseNoMemoryExpensiveCodec (called from LuceneTestCaseRunner):
+  
+  private static final List<Codec> disabledCodecs = new ArrayList<Codec>();
+  
+  static synchronized void disableMemoryExpensiveCodecs() {
+    final CodecProvider cp = CodecProvider.getDefault();
+    if (cp instanceof RandomCodecProvider) {
+      final RandomCodecProvider rcp = (RandomCodecProvider) cp;
+      disabledCodecs.add(rcp.lookup("Memory"));
+      disabledCodecs.add(rcp.lookup("SimpleText"));
+      for (final Codec c : disabledCodecs) {
+        rcp.unregister(c);
+      }
+    }
+  }
+  
+  static synchronized void reenableMemoryExpensiveCodecs() {
+    final CodecProvider cp = CodecProvider.getDefault();
+    if (cp instanceof RandomCodecProvider) {
+      for (final Codec c : disabledCodecs) {
+        ((RandomCodecProvider) cp).register(c);
+      }
+    }
+    disabledCodecs.clear();
+  }
 
   // randomly picks from core and test codecs
   static String pickRandomCodec(Random rnd) {
@@ -1418,6 +1444,14 @@
   @Retention(RetentionPolicy.RUNTIME)
   public @interface Nightly {}
 
+  /**
+   * Annotation for tests that should only use codecs that are not memory expensive (avoid SimpleText, MemoryCodec).
+   */
+  @Documented
+  @Inherited
+  @Retention(RetentionPolicy.RUNTIME)
+  public @interface UseNoMemoryExpensiveCodec {}
+
   @Ignore("just a hack")
   public final void alwaysIgnoredTestMethod() {}
 }
Index: lucene/src/test-framework/org/apache/lucene/util/LuceneTestCaseRunner.java
===================================================================
--- lucene/src/test-framework/org/apache/lucene/util/LuceneTestCaseRunner.java	(revision 1177807)
+++ lucene/src/test-framework/org/apache/lucene/util/LuceneTestCaseRunner.java	(working copy)
@@ -26,6 +26,7 @@
 import java.util.Random;
 
 import org.apache.lucene.util.LuceneTestCase.Nightly;
+import org.apache.lucene.util.LuceneTestCase.UseNoMemoryExpensiveCodec;
 import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.Description;
@@ -131,26 +132,36 @@
     // only print iteration info if the user requested more than one iterations
     final boolean verbose = VERBOSE && TEST_ITER > 1;
     
-    final int currentIter[] = new int[1];
-    arg1.addListener(new RunListener() {
-      @Override
-      public void testFailure(Failure failure) throws Exception {
+    // avoid some codecs if annotation present
+    final boolean useNoMemoryExpensiveCodec = arg0.getAnnotation(UseNoMemoryExpensiveCodec.class) != null;
+    try {
+      if (useNoMemoryExpensiveCodec) {
+        System.err.println("NOTE: Using no memory-expensive random codecs for '" + arg0.getName() + "' unless explicitely selected.");
+        LuceneTestCase.disableMemoryExpensiveCodecs();
+      }
+      final int currentIter[] = new int[1];
+      arg1.addListener(new RunListener() {
+        @Override
+        public void testFailure(Failure failure) throws Exception {
+          if (verbose) {
+            System.out.println("\nNOTE: iteration " + currentIter[0] + " failed! ");
+          }
+        }
+      });
+      for (int i = 0; i < TEST_ITER; i++) {
+        currentIter[0] = i;
         if (verbose) {
-          System.out.println("\nNOTE: iteration " + currentIter[0] + " failed! ");
+          System.out.println("\nNOTE: running iter=" + (1+i) + " of " + TEST_ITER);
         }
-      }
-    });
-    for (int i = 0; i < TEST_ITER; i++) {
-      currentIter[0] = i;
-      if (verbose) {
-        System.out.println("\nNOTE: running iter=" + (1+i) + " of " + TEST_ITER);
-      }
-      super.runChild(arg0, arg1);
-      if (LuceneTestCase.testsFailed) {
-        if (i >= TEST_ITER_MIN - 1) { // XXX is this still off-by-one?
-          break;
+        super.runChild(arg0, arg1);
+        if (LuceneTestCase.testsFailed) {
+          if (i >= TEST_ITER_MIN - 1) { // XXX is this still off-by-one?
+            break;
+          }
         }
       }
+    } finally {
+      LuceneTestCase.reenableMemoryExpensiveCodecs();
     }
   }
   
Index: lucene/src/test/org/apache/lucene/index/TestLongPostings.java
===================================================================
--- lucene/src/test/org/apache/lucene/index/TestLongPostings.java	(revision 1177807)
+++ lucene/src/test/org/apache/lucene/index/TestLongPostings.java	(working copy)
@@ -75,6 +75,7 @@
     }
   }
 
+  @UseNoMemoryExpensiveCodec
   public void testLongPostings() throws Exception {
     assumeFalse("Too slow with SimpleText codec at night", TEST_NIGHTLY && CodecProvider.getDefault().getFieldCodec("field").equals("SimpleText"));
     assumeFalse("Too slow with Memory codec at night", TEST_NIGHTLY && CodecProvider.getDefault().getFieldCodec("field").equals("Memory"));
Index: lucene/src/test/org/apache/lucene/index/TestTermsEnum.java
===================================================================
--- lucene/src/test/org/apache/lucene/index/TestTermsEnum.java	(revision 1177807)
+++ lucene/src/test/org/apache/lucene/index/TestTermsEnum.java	(working copy)
@@ -184,6 +184,7 @@
   }
 
   // Tests Terms.intersect
+  @UseNoMemoryExpensiveCodec
   public void testIntersectRandom() throws IOException {
 
     final Directory dir = newDirectory();
Index: lucene/src/test/org/apache/lucene/util/automaton/TestCompiledAutomaton.java
===================================================================
--- lucene/src/test/org/apache/lucene/util/automaton/TestCompiledAutomaton.java	(revision 1177807)
+++ lucene/src/test/org/apache/lucene/util/automaton/TestCompiledAutomaton.java	(working copy)
@@ -19,6 +19,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
@@ -30,12 +31,20 @@
 public class TestCompiledAutomaton extends LuceneTestCase {
 
   private CompiledAutomaton build(String... strings) {
+    final List<BytesRef> terms = new ArrayList<BytesRef>();
+    for(String s : strings) {
+      terms.add(new BytesRef(s));
+    }
+    Collections.sort(terms);
+    final Automaton a = DaciukMihovAutomatonBuilder.build(terms);
+    /*
     final List<Automaton> as = new ArrayList<Automaton>();
     for(String s : strings) {
       as.add(BasicAutomata.makeString(s));
     }
     Automaton a = BasicOperations.union(as);
     a.determinize();
+    */
     return new CompiledAutomaton(a, true, false);
   }
 
@@ -93,7 +102,7 @@
   }
 
   public void testRandom() throws Exception {
-    final int numTerms = atLeast(1000);
+    final int numTerms = atLeast(400);
     final Set<String> terms = new HashSet<String>();
     while(terms.size() != numTerms) {
       terms.add(randomString());
@@ -107,7 +116,7 @@
   }
 
   public void testBasic() throws Exception {
-    CompiledAutomaton c = build("foo", "fob", "goo");
+    CompiledAutomaton c = build("fob", "foo", "goo");
     testFloor(c, "goo", "goo");
     testFloor(c, "ga", "foo");
     testFloor(c, "g", "foo");
Index: lucene/src/test/org/apache/lucene/util/fst/TestFSTs.java
===================================================================
--- lucene/src/test/org/apache/lucene/util/fst/TestFSTs.java	(revision 1177807)
+++ lucene/src/test/org/apache/lucene/util/fst/TestFSTs.java	(working copy)
@@ -1009,6 +1009,7 @@
 
   // Build FST for all unique terms in the test line docs
   // file, up until a time limit
+  @UseNoMemoryExpensiveCodec
   public void testRealTerms() throws Exception {
 
     final String defaultCodec = CodecProvider.getDefault().getDefaultFieldCodec();