From 1a166bc4c98282acc24e4cf708511d9f412644ce Mon Sep 17 00:00:00 2001
From: unknown <tomas@whalegate.ndb.mysql.com>
Date: Sun, 3 Jun 2007 19:30:37 +0200
Subject: [PATCH] Bug#20612.

storage/ndb/src/kernel/blocks/pgman.cpp:
  a) in one case pl_queue.remove(ptr) was not followed
  by state &= ~ Page_entry::ONQUEUE.

  b) when collecting initial hot entries have to remove
  from queue if somehow got there.

  b) is easy to get with large buffer cache (256M).
  a) or b) is probably cause of bug#20612.
---
 storage/ndb/src/kernel/blocks/pgman.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/storage/ndb/src/kernel/blocks/pgman.cpp b/storage/ndb/src/kernel/blocks/pgman.cpp
index 72333856cf1..78bc70427a9 100644
--- a/storage/ndb/src/kernel/blocks/pgman.cpp
+++ b/storage/ndb/src/kernel/blocks/pgman.cpp
@@ -669,6 +669,7 @@ Pgman::lirs_reference(Ptr<Page_entry> ptr)
         jam();
         move_cleanup_ptr(ptr);
         pl_queue.remove(ptr);
+        state &= ~ Page_entry::ONQUEUE;
       }
       if (state & Page_entry::BOUND)
       {
@@ -699,6 +700,12 @@ Pgman::lirs_reference(Ptr<Page_entry> ptr)
     pl_stack.add(ptr);
     state |= Page_entry::ONSTACK;
     state |= Page_entry::HOT;
+    // it could be on queue already
+    if (state & Page_entry::ONQUEUE) {
+      jam();
+      pl_queue.remove(ptr);
+      state &= ~Page_entry::ONQUEUE;
+    }
   }
 
   set_page_state(ptr, state);