MySQL Bugs: #35749: Test 'query_cache_debug' fails with "Unknown thread id: 0"

Bug #35749	Test 'query_cache_debug' fails with "Unknown thread id: 0"
Submitted:	1 Apr 2008 17:49	Modified:	12 Apr 2008 13:39
Reporter:	Kent Boortz	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Query Cache	Severity:	S2 (Serious)
Version:		OS:	FreeBSD (6.0)
Assigned to:	Kent Boortz	CPU Architecture:	Any

Description:
Running a debug enabled "mysqld" (mysqld-debug) on
FreeBSD 6.0 x86 32bit makes the test 'query_cache_debug'
fail with

main.query_cache_debug         [ fail ]

mysqltest: At line 36: query 'kill query @thread_id' failed: 1094: Unknown thread id: 0

The result from queries just before the failure was:
< snip >
set global query_cache_size= 1024*1024*512;
Warnings:
Warning 1282    Query cache failed to set size 536870912; new query cache size is 0
drop table if exists t1;
create table t1 (a varchar(100));
insert into t1 values ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb');
Activate debug hook and attempt to retrieve the statement from the cache.
set session debug='+d,wait_in_query_cache_insert';
select SQL_CACHE * from t1;;
Timeout in wait_condition.inc for select count(*)= 1 from information_schema.processlist where state= 'wait_in_query_cache_insert'
On a second connection; clear the query cache.
show status like 'Qcache_queries_in_cache';
Variable_name   Value
Qcache_queries_in_cache 0
set global query_cache_size= 0;
Signal the debug hook to release the lock.
select id from information_schema.processlist where state='wait_in_query_cache_insert' into @thread_id;
Warnings:
Warning 1329    No data - zero rows fetched, selected, or processed
kill query @thread_id;

How to repeat:
Run the test case using a debug enabled "mysqld"

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/44763

ChangeSet@1.2564, 2008-04-02 00:43:17+02:00, kent@mysql.com +5 -0
  mysqld.cc:
    Corrects build problems embedded on Windows
  Makefile.am:
    Install .sym or mysqld-debug if exists
  query_cache_debug.test, query_cache_debug.result:
    Set more resonable query cache size (bug#35749)
  CMakeLists.txt:
    Added missing stacktrace.c

Change in testing only, no user changes to document. Closed w/o further action.

Pushed into 5.1.25-rc

Pushed into 6.0.6-alpha