heikki@127:~/mysql-4.1.16/innobase/fil$ diff -bu fil0filold.c fil0fil.c
--- fil0filold.c        2006-01-09 20:53:19.000000000 +0200
+++ fil0fil.c   2006-01-10 21:07:59.549654448 +0200
@@ -179,6 +179,11 @@
        hash_node_t     name_hash;/* hash chain the name_hash table */
        rw_lock_t       latch;  /* latch protecting the file space storage
                                allocation */
+       UT_LIST_NODE_T(fil_space_t) unflushed_spaces;
+                               /* list of spaces with at least one unflushed
+                               file we have written to */
+       ibool           is_in_unflushed_spaces; /* TRUE if this space is
+                               currently in the list above */
        UT_LIST_NODE_T(fil_space_t) space_list;
                                /* list of all spaces */
        ibuf_data_t*    ibuf_data;
@@ -211,6 +216,12 @@
                                        not put to this list: they are opened
                                        after the startup, and kept open until
                                        shutdown */
+       UT_LIST_BASE_NODE_T(fil_space_t) unflushed_spaces;
+                                       /* base node for the list of those
+                                       tablespaces whose files contain
+                                       unflushed writes; those spaces have
+                                       at least one file node where
+                                       modification_counter > flush_counter */
        ulint           n_open;         /* number of files currently open */
        ulint           max_n_open;     /* n_open is not allowed to exceed
                                        this */
@@ -387,6 +398,35 @@
        return(space->ibuf_data);
 }

+/**************************************************************************
+Checks if all the file nodes in a space are flushed. The caller must hold
+the fil_system mutex. */
+static
+ibool
+fil_space_is_flushed(
+/*=================*/
+                               /* out: TRUE if all are flushed */
+       fil_space_t*    space)  /* in: space */
+{
+       fil_system_t*   system  = fil_system;
+       fil_node_t*     node;
+
+       ut_ad(mutex_own(&(system->mutex)));
+
+       node = UT_LIST_GET_FIRST(space->chain);
+
+       while (node) {
+               if (node->modification_counter > node->flush_counter) {
+
+                       return(FALSE);
+               }
+
+               node = UT_LIST_GET_NEXT(chain, node);
+       }
+
+       return(TRUE);
+}
+
 /***********************************************************************
 Appends a new file to the chain of files of a space. File must be closed. */

@@ -839,6 +879,16 @@

                node->modification_counter = node->flush_counter;

+               if (fil_space_is_flushed(space)
+                   && space->is_in_unflushed_spaces) {
+
+                       space->is_in_unflushed_spaces = FALSE;
+
+                       UT_LIST_REMOVE(unflushed_spaces,
+                                       system->unflushed_spaces,
+                                       space);
+               }
+
                fil_node_close_file(node, system);
        }

@@ -1002,6 +1052,8 @@

        HASH_INSERT(fil_space_t, name_hash, system->name_hash,
                                                ut_fold_string(name), space);
+       space->is_in_unflushed_spaces = FALSE;
+
        UT_LIST_ADD_LAST(space_list, system->space_list, space);

        mutex_exit(&(system->mutex));
@@ -1097,6 +1149,11 @@
        HASH_DELETE(fil_space_t, name_hash, system->name_hash,
                                           ut_fold_string(space->name), space);

+       if (space->is_in_unflushed_spaces) {
+               UT_LIST_REMOVE(unflushed_spaces, system->unflushed_spaces,
+                                                               space);
+       }
+
        UT_LIST_REMOVE(space_list, system->space_list, space);

        ut_a(space->magic_n == FIL_SPACE_MAGIC_N);
@@ -1248,6 +1305,7 @@

        system->tablespace_version = 0;

+       UT_LIST_INIT(system->unflushed_spaces);
        UT_LIST_INIT(system->space_list);

        return(system);
@@ -3732,6 +3790,14 @@
        if (type == OS_FILE_WRITE) {
                system->modification_counter++;
                node->modification_counter = system->modification_counter;
+
+               if (!node->space->is_in_unflushed_spaces) {
+
+                       node->space->is_in_unflushed_spaces = TRUE;
+                       UT_LIST_ADD_FIRST(unflushed_spaces,
+                                       system->unflushed_spaces,
+                                       node->space);
+               }
        }

        if (node->n_pending == 0 && node->space->purpose == FIL_TABLESPACE
@@ -4145,6 +4211,16 @@
 skip_flush:
                        if (node->flush_counter < old_mod_counter) {
                                node->flush_counter = old_mod_counter;
+
+                               if (fil_space_is_flushed(space)
+                                   && space->is_in_unflushed_spaces) {
+
+                                       space->is_in_unflushed_spaces = FALSE;
+
+                                       UT_LIST_REMOVE(unflushed_spaces,
+                                               system->unflushed_spaces,
+                                               space);
+                               }
                        }

                        if (space->purpose == FIL_TABLESPACE) {
@@ -4176,7 +4252,7 @@

        mutex_enter(&(system->mutex));

-       space = UT_LIST_GET_FIRST(system->space_list);
+       space = UT_LIST_GET_FIRST(system->unflushed_spaces);

        while (space) {
                if (space->purpose == purpose && !space->is_being_deleted) {
@@ -4192,7 +4268,7 @@

                        space->n_pending_flushes--;
                }
-               space = UT_LIST_GET_NEXT(space_list, space);
+               space = UT_LIST_GET_NEXT(unflushed_spaces, space);
        }

        mutex_exit(&(system->mutex));