update the tick counter on startup with ticks from journals

arangod/VocBase/collection.c

@@ -571,6 +571,36 @@ static bool CloseDataFiles (const TRI_vector_pointer_t* const files) {
   return result;
 }
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief iterate over a set of datafiles
+/// note: the files will be opened and closed 
+////////////////////////////////////////////////////////////////////////////////
+
+static bool IterateFiles (TRI_vector_string_t* vector,
+                          bool (*iterator)(TRI_df_marker_t const*, void*, TRI_datafile_t*, bool)) {
+  size_t i, n;
+  
+  n = vector->_length;
+
+  for (i = 0; i < n ; ++i) {
+    TRI_datafile_t* datafile;
+    char* filename;
+
+    filename = TRI_AtVectorString(vector, i);
+    LOG_DEBUG("iterating over collection journal file '%s'", filename);
+    datafile = TRI_OpenDatafile(filename);
+
+    if (datafile != NULL) {
+      TRI_IterateDatafile(datafile, iterator, NULL, true);
+      TRI_CloseDatafile(datafile);
+      TRI_FreeDatafile(datafile);
+    }
+  }
+
+  return true;
+}
+
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @}
 ////////////////////////////////////////////////////////////////////////////////
@@ -1290,36 +1320,22 @@ void TRI_DestroyFileStructureCollection (TRI_col_file_structure_t* info) {
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief iterate over the markers incollection journals journal
 ///
-/// we do this on startup to find the most recent tick values
+/// this function is called on server startup for all collections
 ////////////////////////////////////////////////////////////////////////////////
 
-bool TRI_IterateJournalsCollection (const char* const path,
-                                    bool (*iterator)(TRI_df_marker_t const*, void*, TRI_datafile_t*, bool)) {
+bool TRI_IterateStartupCollection (const char* const path,
+                                   bool (*iterator)(TRI_df_marker_t const*, void*, TRI_datafile_t*, bool)) {
+
   TRI_col_file_structure_t structure = ScanCollectionDirectory(path);
-  TRI_vector_string_t* vector = &structure._journals;
-  size_t n = vector->_length;
-
-  if (n > 0) {
-    size_t i;
-
-    for (i = 0; i < n ; ++i) {
-      TRI_datafile_t* datafile;
-      char* filename;
-
-      filename = TRI_AtVectorString(vector, i);
-      LOG_DEBUG("iterating over collection journal file '%s'", filename);
-      datafile = TRI_OpenDatafile(filename);
-      if (datafile != NULL) {
-        TRI_IterateDatafile(datafile, iterator, NULL, true);
-        TRI_CloseDatafile(datafile);
-        TRI_FreeDatafile(datafile);
-      }
-    }
-  }
+  bool result;
 
+  // iterate of journals & compactors, not datafiles
+  result  = IterateFiles(&structure._journals, iterator);
+  result &= IterateFiles(&structure._compactors, iterator);
+  
   TRI_DestroyFileStructureCollection(&structure);
 
-  return true;
+  return result;
 }
 
 ////////////////////////////////////////////////////////////////////////////////

arangod/VocBase/collection.h

@@ -427,9 +427,10 @@ void TRI_DestroyFileStructureCollection (TRI_col_file_structure_t*);
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief iterate over markers in collection journals
+/// this function is called on server startup for all collections
 ////////////////////////////////////////////////////////////////////////////////
 
-bool TRI_IterateJournalsCollection (const char* const,
+bool TRI_IterateStartupCollection (const char* const,
                                     bool (*)(TRI_df_marker_t const*, void*, TRI_datafile_t*, bool));
 
 ////////////////////////////////////////////////////////////////////////////////

arangod/VocBase/vocbase.c

@@ -211,6 +211,18 @@ static bool EqualKeyCollectionName (TRI_associative_pointer_t* array, void const
 /// @{
 ////////////////////////////////////////////////////////////////////////////////
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief updates the tick counter, without using a lock
+////////////////////////////////////////////////////////////////////////////////
+
+static void UpdateTick (TRI_voc_tick_t tick) {
+  TRI_voc_tick_t s = tick >> 16;
+
+  if (CurrentTick < s) {
+    CurrentTick = s;
+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief free the memory associated with a collection
 ////////////////////////////////////////////////////////////////////////////////
@@ -611,6 +623,22 @@ static TRI_vocbase_col_t* AddCollection (TRI_vocbase_t* vocbase,
   return collection;
 }
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief this iterator is called on startup for journal and compactor file
+/// of a collection
+/// it will check the ticks of all markers and update the internal tick 
+/// counter accordingly
+////////////////////////////////////////////////////////////////////////////////
+
+static bool StartupIterator (TRI_df_marker_t const* marker, 
+                             void* data, 
+                             TRI_datafile_t* datafile, 
+                             bool journal) {
+  UpdateTick(marker->_tick);
+  
+  return true;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief scans a directory and loads all collections
 ////////////////////////////////////////////////////////////////////////////////
@@ -667,7 +695,7 @@ static int ScanPath (TRI_vocbase_t* vocbase, char const* path) {
       res = TRI_LoadCollectionInfo(file, &info, true);
 
       if (res == TRI_ERROR_NO_ERROR) {
-        TRI_UpdateTickVocBase(info._cid);
+        UpdateTick(info._cid);
       }
 
       if (res != TRI_ERROR_NO_ERROR) {
@@ -724,6 +752,8 @@ static int ScanPath (TRI_vocbase_t* vocbase, char const* path) {
           TRI_vocbase_col_t* c;
 
           c = AddCollection(vocbase, type, info._name, info._cid, file);
+          
+          TRI_IterateStartupCollection(file, StartupIterator);
 
           if (c == NULL) {
             LOG_ERROR("failed to add document collection from '%s'", file);
@@ -971,14 +1001,8 @@ TRI_voc_tick_t TRI_NewTickVocBase () {
 ////////////////////////////////////////////////////////////////////////////////
 
 void TRI_UpdateTickVocBase (TRI_voc_tick_t tick) {
-  TRI_voc_tick_t s = tick >> 16;
-
   TRI_LockSpin(&TickLock);
-
-  if (CurrentTick < s) {
-    CurrentTick = s;
-  }
-
+  UpdateTick(tick);
   TRI_UnlockSpin(&TickLock);
 }