diff --git a/src/handlers/base.py b/src/handlers/base.py
index 9f35a386..4ba22a91 100644
--- a/src/handlers/base.py
+++ b/src/handlers/base.py
@@ -82,9 +82,16 @@ def __init__(self, *args, **kwargs):
     def check_origin(self, _: str) -> bool:
         return True
 
+    async def cleanup(self):
+        await self.p.unsubscribe()
+        if self.task:
+            self.task.cancel()
+
+        await self.p.aclose()
+        await self.rs.aclose()
+
     def on_close(self) -> None:
-        self.task.cancel()
-        asyncio.create_task(self.rs.aclose())
+        asyncio.create_task(self.cleanup())
 
 
 def reqenv(func):
diff --git a/src/handlers/rank.py b/src/handlers/rank.py
index 33734a01..c7ba3af3 100644
--- a/src/handlers/rank.py
+++ b/src/handlers/rank.py
@@ -37,25 +37,26 @@ async def get(self, pro_id):
                         "account"."name" AS "acct_name",
                         "challenge_state"."runtime",
                         "challenge_state"."memory",
-                        ROUND("challenge_state"."rate", "problem"."rate_precision")
+                        ROUND("challenge_state"."rate", "problem"."rate_precision") AS rate
 
                     FROM "challenge"
+
+                    INNER JOIN "problem"
+                    ON "challenge"."pro_id" = "problem"."pro_id" AND "problem"."pro_id" = $1
+
                     INNER JOIN "account"
                     ON "challenge"."acct_id"="account"."acct_id"
 
                     INNER JOIN "challenge_state"
                     ON "challenge"."chal_id"="challenge_state"."chal_id"
 
-                    INNER JOIN "problem"
-                    ON "challenge"."pro_id" = $1
-
                     WHERE "challenge_state"."state"={ChalConst.STATE_AC}
 
-                    ORDER BY "challenge"."acct_id" ASC, "challenge_state"."rate" ASC,
+                    ORDER BY "challenge"."acct_id" ASC, "challenge_state"."rate" DESC,
                     "challenge_state"."runtime" ASC, "challenge_state"."memory" ASC,
                     "challenge"."timestamp" ASC
                 ) temp
-                ORDER BY "runtime" ASC, "memory" ASC,
+                ORDER BY "rate" DESC, "runtime" ASC, "memory" ASC,
                 "timestamp" ASC, "acct_id" ASC OFFSET $2 LIMIT $3;
                 '''
                 ,
diff --git a/src/server.py b/src/server.py
index 4dca6006..9445602a 100644
--- a/src/server.py
+++ b/src/server.py
@@ -33,11 +33,11 @@ def stop_loop(deadline):
             for task in asyncio.all_tasks():
                 task.cancel()
 
-            io_loop.add_callback(db.close)
-            io_loop.add_callback(rs.aclose)
-            io_loop.add_callback(pool.aclose)
-            io_loop.add_callback(JudgeServerClusterService.inst.disconnect_all_server)
-            io_loop.stop()
+            asyncio.create_task(db.close())
+            asyncio.create_task(rs.aclose())
+            asyncio.create_task(pool.aclose())
+            asyncio.create_task(JudgeServerClusterService.inst.disconnect_all_server())
+            io_loop.add_callback(io_loop.stop)
 
             print('Shutdown finally')
 
diff --git a/src/services/contests.py b/src/services/contests.py
index 381d1fd8..c922af11 100644
--- a/src/services/contests.py
+++ b/src/services/contests.py
@@ -247,7 +247,7 @@ async def get_ioi2013_scores(self, contest_id: int, pro_id: int, before_time: da
                 "challenge"."pro_id",
                 "challenge"."acct_id",
                 "challenge"."timestamp",
-                ROUND("challenge_state"."rate", problem.rate_precision),
+                ROUND("challenge_state"."rate", problem.rate_precision) AS rate,
 
                 ROW_NUMBER() OVER (
                     PARTITION BY "challenge"."pro_id", "challenge"."acct_id"
diff --git a/src/static/templ/pro.html b/src/static/templ/pro.html
index 32519765..e9bb3931 100644
--- a/src/static/templ/pro.html
+++ b/src/static/templ/pro.html
@@ -20,7 +20,7 @@
 
     function init() {
         let PDFJS = pdfjsLib;
-        PDFJS.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/4.7.76/pdf.worker.min.mjs';
+        PDFJS.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/4.7.76/pdf.worker.min.mjs';
 
         $('#tags').keydown(function(event) {
             if (event.which == 13) // return
diff --git a/src/utils/htmlgen.py b/src/utils/htmlgen.py
index e54dc657..3f92f98f 100644
--- a/src/utils/htmlgen.py
+++ b/src/utils/htmlgen.py
@@ -17,4 +17,4 @@ def set_page_title(title: str, site_title: str = None):
     """
 
 def markdown_escape(code: str) -> str:
-    return code.replace('`', '\\`').replace('\\', '\\\\')
+    return code.replace('\\', '\\\\').replace('`', '\\`')