It's trying to change the mount-point property during the initial load, and
actually crashing in the "rhythmdb_get_readonly (db) == FALSE" assert (not later
as gdb says).

Still occurs with current CVS HEAD, it's trying to update the "last seen" entry
this time:

+ Trace 60677

More interesting is what the second thread is doing:

+ Trace 60678

From the original crashing thread:
(gdb) frame 6

+ Trace 60680

$1 = (RhythmDBEntry *) 0x860e620
(gdb) p entry->location
$2 = 0x860f8a8
"file:///home/hadess/Desktop/data/Music/Albums/Gorillaz%20-%20G%20Sides/02.%20Gorillaz%20-%20Dracula.mp3"

We're not even processing the same file.

I've pushed a small fix that might do something:
        * rhythmdb/rhythmdb.c: (rhythmdb_save_thread_main):
        send a RHYTHMDB_EVENT_DB_SAVED event even if we don't have to save
        the database, otherwise the read counter doesn't get decreased

I think there's a fix in my playbin branch which I haven't pushed anywhere else,
I'll have to check that.

Created attachment 47414 [details] [review]
Patch from my playbin branch

What this patch does is to make sure that the database is always modified from
the main thread, and it also makes sure the database isn't read-only before
modifying it. It queues database changes to be able to process them later if the
database is read-only. This patch fixes the startup crashes as far as I could
see, however I have seen a few big slowdowns at startup with it applied but I
didn't really dig further to try to figure out what was going on (from the
console trace, it seemed lots of stuff was being queued to be processed later,
but I dunno why it happened nor why it slowed things down).

2005-06-12  Christophe Fergeau  <teuf@gnome.org>

        * lib/rb-util.c: (rb_is_main_thread), (rb_threads_init):
        * lib/rb-util.h:
        * rhythmdb/rhythmdb.c: (rhythmdb_event_free), (rhythmdb_shutdown),
        (rhythmdb_read_enter), (rhythmdb_read_leave),
        (timeout_rhythmdb_commit), (set_metadata_string_default_unknown),
        (set_props_from_metadata), (rhythmdb_process_stat_event),
        (rhythmdb_process_metadata_load),
        (rhythmdb_process_queued_entry_set_event),
        (rhythmdb_process_events), (action_thread_main),
        (rhythmdb_entry_sync), (rhythmdb_entry_set_internal),
        (rhythmdb_entry_queue_set), (rhythmdb_entry_set),
        (rhythmdb_prop_get_type), (entry_volume_mounted_or_unmounted),
        (rhythmdb_entry_set_mount_point), (rhythmdb_entry_set_visibility):
        * rhythmdb/rhythmdb.h:
        * shell/main.c: (main):
        * sources/rb-source.c: (rb_source_update_play_statistics):
        * widgets/rb-entry-view.c: (rb_entry_view_rated_cb): reimplement
        rhythmdb_entry_queue_set, this should fix some crashes when doing
        a rhythmdb_entry_set while the db is read-only