issue #650: Randonmess of any() should be improved

CHANGELOG

@@ -1,6 +1,8 @@
 v1.5.x (XXXX-XX-XX)
 -------------------
 
+* fixed issue #650: Randonmess of any() should be improved
+
 * made AQL `DOCUMENT()` function polymorphic and work with just one parameter.
 
   This allows using the `DOCUMENT` function like this:
@@ -150,6 +152,12 @@ v1.4.0 (2013-10-29)
 v1.4.0-beta2 (2013-10-14)
 -------------------------
 
+* fixed compaction on Windows 
+
+  The compaction on Windows did not ftruncate the cleaned datafiles to a smaller size.
+  This has been fixed so not only the content of the files is cleaned but also files
+  are re-created with potentially smaller sizes.
+
 * only the following system collections will be excluded from replication from now on:
   - `_replication`
   - `_trx`

UnitTests/Makefile.unittests

@@ -282,7 +282,6 @@ endif
 
 SHELL_COMMON = \
                @top_srcdir@/js/common/tests/shell-require.js \
-               @top_srcdir@/js/common/tests/shell-transactions.js \
                @top_srcdir@/js/common/tests/shell-aqlfunctions.js \
                @top_srcdir@/js/common/tests/shell-attributes.js \
                @top_srcdir@/js/common/tests/shell-collection.js \
@@ -296,6 +295,7 @@ SHELL_COMMON = \
                @top_srcdir@/js/common/tests/shell-keygen.js \
                @top_srcdir@/js/common/tests/shell-simple-query.js \
                @top_srcdir@/js/common/tests/shell-statement.js \
+               @top_srcdir@/js/common/tests/shell-transactions.js \
                @top_srcdir@/js/common/tests/shell-unload.js \
                @top_srcdir@/js/common/tests/shell-users.js \
                @top_srcdir@/js/common/tests/shell-index.js \
@@ -314,6 +314,7 @@ SHELL_SERVER_ONLY = \
                @top_srcdir@/js/server/tests/compaction.js \
                @top_srcdir@/js/server/tests/transactions.js \
                @top_srcdir@/js/server/tests/routing.js \
+               @top_srcdir@/js/server/tests/shell-any.js \
                @top_srcdir@/js/common/tests/shell-bitarray-index.js \
                @top_srcdir@/js/server/tests/shell-database.js \
                @top_srcdir@/js/common/tests/shell-foxx.js \

arangod/Utils/Transaction.h

@@ -480,7 +480,7 @@ namespace triagens {
             void** beg = primary->_primaryIndex._table;
 
             while (beg[pos] == 0) {
-              pos = (pos + 1) % total;
+              pos = TRI_UInt32Random() % total;
             }
 
             *mptr = *((TRI_doc_mptr_t*) beg[pos]);

js/server/tests/shell-any.js

@@ -0,0 +1,275 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test the collection interface
+///
+/// @file
+///
+/// DISCLAIMER
+///
+/// Copyright 2010-2012 triagens GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+/// @author Copyright 2012, triAGENS GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+var jsunity = require("jsunity");
+
+var arangodb = require("org/arangodb");
+var internal = require("internal");
+var db = arangodb.db;
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                               any
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test suite
+////////////////////////////////////////////////////////////////////////////////
+
+function AnySuite () {
+  var cn = "example";
+  var c;
+
+  var threshold = 15; // maximum tolerated stddev for distribution
+
+  var stddev = function (dist) {
+    var v;
+    var sum = 0;
+    var count = 0;
+
+    for (v in dist) {
+      if (dist.hasOwnProperty(v)) {
+        sum += dist[v];
+        count++;
+      }
+    }
+
+    var avg = sum / count;
+    var sum2 = 0;
+
+    for (v in dist) {
+      if (dist.hasOwnProperty(v)) {
+        var d = dist[v] - avg;
+        sum2 += d * d;
+      }
+    }
+
+    return Math.sqrt(sum2 / count);
+  };
+
+  var getDistribution = function (n, rng) {
+    var dist = { };
+    var i;
+
+    for (i = 0; i < n; ++i) {
+      var pick = rng();
+
+      if (dist.hasOwnProperty(pick)) {
+        dist[pick]++;
+      }
+      else {
+        dist[pick] = 1;
+      }
+    }
+
+    return dist;
+  };
+
+  return {
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief set up
+////////////////////////////////////////////////////////////////////////////////
+
+    setUp : function () {
+      db._drop(cn);
+      c = db._create(cn);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief tear down
+////////////////////////////////////////////////////////////////////////////////
+
+    tearDown : function () {
+      db._drop(cn);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of Math.random()
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyNative : function () {
+      var i, n;
+
+      n = 100;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+
+      var dist = getDistribution(n * 100, function () {
+        return parseInt(Math.random() * 100, 10);
+      });
+
+      assertTrue(stddev(dist) < threshold);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), just one document
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionOne : function () {
+      c.save({ value: 1 });
+
+      var dist = getDistribution(100, function () {
+        return c.any().value;
+      });
+      
+      assertTrue(stddev(dist) <= 0.01);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), few picks
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionFew1 : function () {
+      var i, n;
+
+      n = 3;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+
+      var dist = getDistribution(n * 200, function () {
+        return c.any().value;
+      });
+      
+      assertTrue(stddev(dist) < threshold * 1.5);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), few picks
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionFew2 : function () {
+      var i, n;
+
+      n = 10;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+
+      var dist = getDistribution(n * 100, function () {
+        return c.any().value;
+      });
+      
+      assertTrue(stddev(dist) < threshold);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), more picks
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionMore : function () {
+      var i, n;
+
+      n = 500;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+      
+      var dist = getDistribution(n * 100, function () {
+        return c.any().value;
+      });
+
+      assertTrue(stddev(dist) < threshold);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), with many documents deleted
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionHalf : function () {
+      var i, n;
+
+      n = 500;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+
+      // remove 50 % of entries
+      var d = Math.round(n * 0.5);
+      for (i = 0; i < d; ++i) {
+        c.remove(c.any());
+      }
+
+      var dist = getDistribution(n * 50, function () {
+        return c.any().value;
+      });
+
+      assertTrue(stddev(dist) < threshold);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check entropy of any(), with most documents deleted
+////////////////////////////////////////////////////////////////////////////////
+
+    testCheckEntropyCollectionSparse : function () {
+      var i, n;
+
+      n = 500;
+
+      for (i = 0; i < n; ++i) {
+        c.save({ value: i });
+      }
+
+      // remove 50 % of entries
+      var d = Math.round(n * 0.95);
+      for (i = 0; i < d; ++i) {
+        c.remove(c.any());
+      }
+
+      var dist = getDistribution(n * 5, function () {
+        return c.any().value;
+      });
+
+      assertTrue(stddev(dist) < threshold);
+    }
+
+  };
+}
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                              main
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief executes the test suite
+////////////////////////////////////////////////////////////////////////////////
+
+jsunity.run(AnySuite);
+
+return jsunity.done();
+
+// Local Variables:
+// mode: outline-minor
+// outline-regexp: "^\\(/// @brief\\|/// @addtogroup\\|// --SECTION--\\|/// @page\\|/// @}\\)"
+// End:
+