[evolution-data-server] CamelStoreSummary: Schedule save rather than save immediately

[Milan Crha <mcrha src gnome org>]

commit cf7cab01492cf367a8ea1422b7b6c298cd235ea8
Author: Milan Crha <mcrha redhat com>
Date:   Wed Jan 25 11:27:56 2012 +0100

    CamelStoreSummary: Schedule save rather than save immediately
    
    There was a regression from commit 5c52fe678f6d, marking multiple
    messages read/unread invoked save on each single message change, which
    had a) performance impact, b) did unnecessary disk writes (with fsync()
    calls). This change fixes it by scheduling save, postponing it
    by 5 seconds from the last connected CamelFolderSummary's count change.

 camel/camel-store-summary.c |   69 +++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 67 insertions(+), 2 deletions(-)
---
diff --git a/camel/camel-store-summary.c b/camel/camel-store-summary.c
index 82324dd..a1379d3 100644
--- a/camel/camel-store-summary.c
+++ b/camel/camel-store-summary.c
@@ -56,6 +56,8 @@ struct _CamelStoreSummaryPrivate {
 	GStaticRecMutex ref_lock;	/* for reffing/unreffing messageinfo's ALWAYS obtain before CAMEL_STORE_SUMMARY_SUMMARY_LOCK */
 
 	GHashTable *folder_summaries; /* CamelFolderSummary->path; doesn't add reference to CamelFolderSummary */
+
+	guint scheduled_save_id;
 };
 
 G_DEFINE_TYPE (CamelStoreSummary, camel_store_summary, CAMEL_TYPE_OBJECT)
@@ -83,6 +85,26 @@ store_summary_finalize (GObject *object)
 	G_OBJECT_CLASS (camel_store_summary_parent_class)->finalize (object);
 }
 
+static void
+store_summary_dispose (GObject *object)
+{
+	CamelStoreSummary *summary = CAMEL_STORE_SUMMARY (object);
+
+	camel_store_summary_lock (summary, CAMEL_STORE_SUMMARY_REF_LOCK);
+	camel_store_summary_lock (summary, CAMEL_STORE_SUMMARY_SUMMARY_LOCK);
+
+	if (summary->priv->scheduled_save_id != 0) {
+		g_source_remove (summary->priv->scheduled_save_id);
+		summary->priv->scheduled_save_id = 0;
+		camel_store_summary_save (summary);
+	}
+
+	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_SUMMARY_LOCK);
+	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_REF_LOCK);
+
+	G_OBJECT_CLASS (camel_store_summary_parent_class)->dispose (object);
+}
+
 static gint
 store_summary_summary_header_load (CamelStoreSummary *summary,
                                    FILE *in)
@@ -285,6 +307,7 @@ camel_store_summary_class_init (CamelStoreSummaryClass *class)
 	g_type_class_add_private (class, sizeof (CamelStoreSummaryPrivate));
 
 	object_class = G_OBJECT_CLASS (class);
+	object_class->dispose = store_summary_dispose;
 	object_class->finalize = store_summary_finalize;
 
 	class->summary_header_load = store_summary_summary_header_load;
@@ -314,6 +337,7 @@ camel_store_summary_init (CamelStoreSummary *summary)
 	summary->folders = g_ptr_array_new ();
 	summary->folders_path = g_hash_table_new (g_str_hash, g_str_equal);
 	summary->priv->folder_summaries = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, g_free);
+	summary->priv->scheduled_save_id = 0;
 
 	g_static_rec_mutex_init (&summary->priv->summary_lock);
 	g_static_rec_mutex_init (&summary->priv->io_lock);
@@ -1099,6 +1123,40 @@ camel_store_summary_unlock (CamelStoreSummary *summary,
 	}
 }
 
+static gboolean
+store_summary_save_timeout (gpointer user_data)
+{
+	CamelStoreSummary *summary = user_data;
+
+	g_return_val_if_fail (summary != NULL, FALSE);
+	g_return_val_if_fail (summary->priv != NULL, FALSE);
+
+	camel_store_summary_lock (summary, CAMEL_STORE_SUMMARY_REF_LOCK);
+	camel_store_summary_lock (summary, CAMEL_STORE_SUMMARY_SUMMARY_LOCK);
+
+	if (summary->priv->scheduled_save_id) {
+		summary->priv->scheduled_save_id = 0;
+		camel_store_summary_save (summary);
+	}
+
+	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_SUMMARY_LOCK);
+	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_REF_LOCK);
+
+	return FALSE;
+}
+
+static void
+store_summary_schedule_save (CamelStoreSummary *summary)
+{
+	g_return_if_fail (summary != NULL);
+	g_return_if_fail (summary->priv != NULL);
+
+	if (summary->priv->scheduled_save_id != 0)
+		g_source_remove (summary->priv->scheduled_save_id);
+
+	summary->priv->scheduled_save_id = g_timeout_add_seconds (5, store_summary_save_timeout, summary);
+}
+
 static void
 store_summary_sync_folder_summary_count_cb (CamelFolderSummary *folder_summary,
                                             GParamSpec *param,
@@ -1131,14 +1189,14 @@ store_summary_sync_folder_summary_count_cb (CamelFolderSummary *folder_summary,
 		if (si->total != new_count) {
 			si->total = new_count;
 			camel_store_summary_touch (summary);
-			camel_store_summary_save (summary);
+			store_summary_schedule_save (summary);
 		}
 	} else if (g_strcmp0 (g_param_spec_get_name (param), "unread-count") == 0) {
 		new_count = camel_folder_summary_get_unread_count (folder_summary);
 		if (si->unread != new_count) {
 			si->unread = new_count;
 			camel_store_summary_touch (summary);
-			camel_store_summary_save (summary);
+			store_summary_schedule_save (summary);
 		}
 	} else {
 		g_warn_if_reached ();
@@ -1243,6 +1301,13 @@ camel_store_summary_disconnect_folder_summary (CamelStoreSummary *summary,
 	g_signal_handlers_disconnect_by_func (folder_summary, G_CALLBACK (store_summary_sync_folder_summary_count_cb), summary);
 	g_hash_table_remove (summary->priv->folder_summaries, folder_summary);
 
+	if (summary->priv->scheduled_save_id != 0) {
+		g_source_remove (summary->priv->scheduled_save_id);
+		summary->priv->scheduled_save_id = 0;
+	}
+
+	camel_store_summary_save (summary);
+
 	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_SUMMARY_LOCK);
 	camel_store_summary_unlock (summary, CAMEL_STORE_SUMMARY_REF_LOCK);