Huge performance boost for the DB queries on the home page.

The queries on the home page weren't bound by dates (which are indexed) or limited by the number of rows returned (despite the tables being a fixed size there). Adding these two filters on each of the queries makes the home page fly. The dates are done w/ a BETWEEN clause, while the limit on the queries is done w/ a normal LIMIT statement. The result takes the page from 3.5s average load time to about 400ms. :D :D :D

diff --git a/xonstat/views/main.py b/xonstat/views/main.py
index 0d90776b4cf1d2f7c0261415e599c8861e606165..ae67aa1d833e377c1e6f5e02f91c0e803befc74e 100755 (executable)
--- a/xonstat/views/main.py
+++ b/xonstat/views/main.py
@@ -22,7 +22,8 @@ def main_index(request):
     duel_ranks = DBSession.query(PlayerRank.player_id, PlayerRank.nick, 
             PlayerRank.elo).\
             filter(PlayerRank.game_type_cd=='duel').\
-            order_by(PlayerRank.rank).all()[0:10]
+            order_by(PlayerRank.rank).\
+            limit(10).all()
 
     duel_ranks = [(player_id, html_colors(nick), elo) \
             for (player_id, nick, elo) in duel_ranks]
@@ -34,7 +35,8 @@ def main_index(request):
     ctf_ranks = DBSession.query(PlayerRank.player_id, PlayerRank.nick, 
             PlayerRank.elo).\
             filter(PlayerRank.game_type_cd=='ctf').\
-            order_by(PlayerRank.rank).all()[0:10]
+            order_by(PlayerRank.rank).\
+            limit(10).all()
 
     ctf_ranks = [(player_id, html_colors(nick), elo) \
             for (player_id, nick, elo) in ctf_ranks]
@@ -46,7 +48,8 @@ def main_index(request):
     dm_ranks = DBSession.query(PlayerRank.player_id, PlayerRank.nick, 
             PlayerRank.elo).\
             filter(PlayerRank.game_type_cd=='dm').\
-            order_by(PlayerRank.rank).all()[0:10]
+            order_by(PlayerRank.rank).\
+            limit(10).all()
 
     dm_ranks = [(player_id, html_colors(nick), elo) \
             for (player_id, nick, elo) in dm_ranks]
@@ -54,16 +57,18 @@ def main_index(request):
     for i in range(leaderboard_count-len(dm_ranks)):
         dm_ranks.append(('-', '-', '-'))
 
+    right_now = datetime.utcnow()
+    back_then = datetime.utcnow() - timedelta(days=leaderboard_lifetime)
+
     # top players by playing time
     top_players = DBSession.query(Player.player_id, Player.nick, 
             func.sum(PlayerGameStat.alivetime)).\
             filter(Player.player_id == PlayerGameStat.player_id).\
             filter(Player.player_id > 2).\
-            filter(PlayerGameStat.create_dt > 
-                    (datetime.utcnow() - timedelta(days=leaderboard_lifetime))).\
+            filter(expr.between(PlayerGameStat.create_dt, back_then, right_now)).\
             order_by(expr.desc(func.sum(PlayerGameStat.alivetime))).\
             group_by(Player.nick).\
-            group_by(Player.player_id).all()[0:10]
+            group_by(Player.player_id).limit(10).all()
 
     top_players = [(player_id, html_colors(nick), score) \
             for (player_id, nick, score) in top_players]
@@ -75,11 +80,10 @@ def main_index(request):
     top_servers = DBSession.query(Server.server_id, Server.name, 
             func.count()).\
             filter(Game.server_id==Server.server_id).\
-            filter(Game.create_dt > 
-                (datetime.utcnow() - timedelta(days=leaderboard_lifetime))).\
+            filter(expr.between(Game.create_dt, back_then, right_now)).\
             order_by(expr.desc(func.count(Game.game_id))).\
             group_by(Server.server_id).\
-            group_by(Server.name).all()[0:10]
+            group_by(Server.name).limit(10).all()
 
     for i in range(leaderboard_count-len(top_servers)):
         top_servers.append(('-', '-', '-'))
@@ -88,11 +92,10 @@ def main_index(request):
     top_maps = DBSession.query(Game.map_id, Map.name, 
             func.count()).\
             filter(Map.map_id==Game.map_id).\
-            filter(Game.create_dt > 
-                (datetime.utcnow() - timedelta(days=leaderboard_lifetime))).\
+            filter(expr.between(Game.create_dt, back_then, right_now)).\
             order_by(expr.desc(func.count())).\
             group_by(Game.map_id).\
-            group_by(Map.name).all()[0:10]
+            group_by(Map.name).limit(10).all()
 
     for i in range(leaderboard_count-len(top_maps)):
         top_maps.append(('-', '-', '-'))
@@ -103,7 +106,8 @@ def main_index(request):
             filter(Game.map_id==Map.map_id).\
             filter(PlayerGameStat.game_id==Game.game_id).\
             filter(PlayerGameStat.rank==1).\
-            order_by(expr.desc(Game.start_dt)).all()[0:recent_games_count]
+            filter(expr.between(Game.create_dt, back_then, right_now)).\
+            order_by(expr.desc(Game.start_dt)).limit(recent_games_count).all()
 
     for i in range(recent_games_count-len(recent_games)):
         recent_games.append(('-', '-', '-', '-'))