bk commit into 5.0 tree (tomas:1.2401) BUG#27560

[tomas]

Below is the list of changes that have just been committed into a local
5.0 repository of tomas. When tomas does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2007-04-02 18:21:05+02:00, tomas@stripped +1 -0
  BUG#27560: Memory usage of mysqld grows while doing nothing
    
  The query-cache watch thread was continually allocating new thread entries on the
  THD MEM_ROOT, not freed until server exit.
    
  Fixed by using a simple array, auto-expanded as necessary.

  sql/ha_ndbcluster.cc@stripped, 2007-04-02 18:21:03+02:00, tomas@stripped +25
-10
    Use a fixed array (auto-expanded as necessary) for temporary copy of open shares,
    don't keep pushing list entries on the THD mem root.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	tomas
# Host:	whalegate.ndb.mysql.com
# Root:	/home/tomas/mysql-5.0-telco-gca

--- 1.301/sql/ha_ndbcluster.cc	2007-03-22 12:42:11 +01:00
+++ 1.302/sql/ha_ndbcluster.cc	2007-04-02 18:21:03 +02:00
@@ -6677,7 +6677,8 @@
     DBUG_RETURN(NULL);
   }
 
-  List<NDB_SHARE> util_open_tables;
+  uint share_list_size= 0;
+  NDB_SHARE **share_list= NULL;
   set_timespec(abstime, 0);
   for (;;)
   {
@@ -6704,7 +6705,22 @@
     /* Lock mutex and fill list with pointers to all open tables */
     NDB_SHARE *share;
     pthread_mutex_lock(&ndbcluster_mutex);
-    for (uint i= 0; i < ndbcluster_open_tables.records; i++)
+    uint i, record_count= ndbcluster_open_tables.records;
+    if (share_list_size < record_count)
+    {
+      NDB_SHARE ** new_share_list= new NDB_SHARE * [record_count];
+      if (!new_share_list)
+      {
+        sql_print_warning("ndb util thread: malloc failure, "
+                          "query cache not maintained properly");
+        pthread_mutex_unlock(&ndbcluster_mutex);
+        goto next;                               // At least do not crash
+      }
+      delete [] share_list;
+      share_list_size= record_count;
+      share_list= new_share_list;
+    }
+    for (i= 0; i < record_count; i++)
     {
       share= (NDB_SHARE *)hash_element(&ndbcluster_open_tables, i);
       share->use_count++; /* Make sure the table can't be closed */
@@ -6713,14 +6729,14 @@
                   i, share->table_name, share->use_count));
 
       /* Store pointer to table */
-      util_open_tables.push_back(share);
+      share_list[i]= share;
     }
     pthread_mutex_unlock(&ndbcluster_mutex);
 
-    /* Iterate through the  open files list */
-    List_iterator_fast<NDB_SHARE> it(util_open_tables);
-    while ((share= it++))
+    /* Iterate through the open files list */
+    for (i= 0; i < record_count; i++)
     {
+      share= share_list[i];
       /* Split tab- and dbname */
       char buf[FN_REFLEN];
       char *tabname, *db;
@@ -6767,10 +6783,7 @@
       /* Decrease the use count and possibly free share */
       free_share(share);
     }
-
-    /* Clear the list of open tables */
-    util_open_tables.empty();
-
+next:
     /* Calculate new time to wake up */
     int secs= 0;
     int msecs= ndb_cache_check_time;
@@ -6793,6 +6806,8 @@
     }
   }
 
+  if (share_list)
+    delete [] share_list;
   thd->cleanup();
   delete thd;
   delete ndb;