--source include/not_embedded.inc --source include/have_query_cache.inc --source include/have_debug.inc # # Bug #30887 Server crashes on SET GLOBAL query_cache_size=0 # flush status; set query_cache_type=DEMAND; set global query_cache_size= 1024*768; --disable_warnings drop table if exists t1; --enable_warnings create table t1 (a varchar(100)); insert into t1 values ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); connect (bug30887con1, localhost, root, ,test); connect (bug30887con2, localhost, root, ,test); connection bug30887con1; --echo Activate debug hook and attempt to retrieve the statement from the cache. set session debug='+d,wait_in_query_cache_insert'; --send select SQL_CACHE * from t1; connection default; let $wait_condition= select count(*)= 1 from information_schema.processlist where state= 'wait_in_query_cache_insert'; --source include/wait_condition.inc connection bug30887con2; --echo On a second connection; clear the query cache. show status like 'Qcache_queries_in_cache'; set global query_cache_size= 0; connection default; --echo Signal the debug hook to release the lock. select id from information_schema.processlist where state='wait_in_query_cache_insert' into @thread_id; kill query @thread_id; --echo Show query cache status. show status like 'Qcache_queries_in_cache'; disconnect bug30887con1; disconnect bug30887con2; set global query_cache_size= 0; use test; drop table t1; # # Bug#41098: Query Cache returns wrong result with concurrent insert # SET @old_concurrent_insert= @@GLOBAL.concurrent_insert; SET @old_query_cache_size= @@GLOBAL.query_cache_size; --disable_warnings DROP TABLE IF EXISTS t1, t2; --enable_warnings CREATE TABLE t1 (a INT); CREATE TABLE t2 (a INT); INSERT INTO t1 VALUES (1),(2),(3); SET GLOBAL concurrent_insert= 1; SET GLOBAL query_cache_size= 1024*512; SET GLOBAL query_cache_type= ON; connect(con1,localhost,root,,test,,); connect(con2,localhost,root,,test,,); connection con1; --echo # Switch to connection con1 SET SESSION debug='+d,wait_after_query_cache_invalidate'; --echo # Send concurrent insert, will wait in the query cache table invalidate --send INSERT INTO t1 VALUES (4) connection default; --echo # Switch to connection default --echo # Wait for concurrent insert to reach the debug point let $wait_condition= SELECT COUNT(*) = 1 FROM INFORMATION_SCHEMA.PROCESSLIST WHERE STATE = "wait_after_query_cache_invalidate" AND INFO = "INSERT INTO t1 VALUES (4)"; --source include/wait_condition.inc connection con2; --echo # Switch to connection con2 --echo # Send SELECT that shouldn't be cached SELECT * FROM t1; connection default; --echo # Switch to connection default --echo # Notify the concurrent insert to proceed SELECT ID FROM INFORMATION_SCHEMA.PROCESSLIST WHERE STATE = 'wait_after_query_cache_invalidate' INTO @thread_id; KILL QUERY @thread_id; connection con1; --echo # Switch to connection con1 --echo # Gather insert result --reap SHOW STATUS LIKE "Qcache_queries_in_cache"; --echo # Test that it's cacheable SELECT * FROM t1; SHOW STATUS LIKE "Qcache_queries_in_cache"; --echo # Disconnect disconnect con1; disconnect con2; connection default; --echo # Restore defaults RESET QUERY CACHE; DROP TABLE t1,t2; SET GLOBAL concurrent_insert= DEFAULT; SET GLOBAL query_cache_size= DEFAULT; SET GLOBAL query_cache_type= DEFAULT; --echo # --echo # Bug43758 Query cache can lock up threads in 'freeing items' state --echo # FLUSH STATUS; SET GLOBAL query_cache_type=DEMAND; SET GLOBAL query_cache_size= 1024*768; --disable_warnings DROP TABLE IF EXISTS t1,t2,t3,t4,t5; --enable_warnings CREATE TABLE t1 (a VARCHAR(100)); CREATE TABLE t2 (a VARCHAR(100)); CREATE TABLE t3 (a VARCHAR(100)); CREATE TABLE t4 (a VARCHAR(100)); CREATE TABLE t5 (a VARCHAR(100)); INSERT INTO t1 VALUES ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); INSERT INTO t2 VALUES ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); INSERT INTO t3 VALUES ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); INSERT INTO t4 VALUES ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); INSERT INTO t5 VALUES ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'); connect (thd2, localhost, root, ,test); connect (thd3, localhost, root, ,test); connect (thd1, localhost, root, ,test); connection thd1; --echo =================================== Connection thd1 --echo ** --echo ** Load Query Cache with a result set and one table. --echo ** SELECT SQL_CACHE * FROM t1; --echo ************************************************************************* --echo ** We want to accomplish the following state: --echo ** - Query cache status: TABLE_FLUSH_IN_PROGRESS --echo ** - THD1: invalidate_table_internal (iterating query blocks) --echo ** - THD2: query_cache_insert (cond_wait) --echo ** - THD3: query_cache_insert (cond_wait) --echo ** - No thread should be holding the structure_guard_mutex. --echo ** --echo ** First step is to place a DELETE-statement on the debug hook just --echo ** before the mutex lock in invalidate_table_internal. --echo ** This will allow new result sets to be written into the QC. --echo ** SET SESSION debug='+d,wait_in_query_cache_invalidate1'; SET SESSION debug='+d,wait_in_query_cache_invalidate2'; --send DELETE FROM t1 WHERE a like '%a%'; connection default; --echo =================================== Connection default --echo ** Assert that the expect process status is obtained. LET $wait_condition= SELECT SQL_NO_CACHE COUNT(*)= 1 FROM information_schema.processlist WHERE state= 'wait_in_query_cache_invalidate1'; --source include/wait_condition.inc -- echo ** connection thd2; --echo =================================== Connection thd2 --echo ** On THD2: Insert a result into the cache. This attempt will be blocked --echo ** because of a debug hook placed just before the mutex lock after which --echo ** the first part of the result set is written. SET SESSION debug='+d,wait_in_query_cache_insert'; --send SELECT SQL_CACHE * FROM t2 UNION SELECT * FROM t3 connection thd3; --echo =================================== Connection thd3 --echo ** On THD3: Insert another result into the cache and block on the same --echo ** debug hook. SET SESSION debug='+d,wait_in_query_cache_insert'; --send SELECT SQL_CACHE * FROM t4 UNION SELECT * FROM t5; connection default; --echo =================================== Connection default --echo ** Assert that the two SELECT-stmt threads to reach the hook. LET $wait_condition= SELECT SQL_NO_CACHE COUNT(*)= 2 FROM information_schema.processlist WHERE state='wait_in_query_cache_insert'; --source include/wait_condition.inc --echo ** --echo ** --echo ** Signal the DELETE thread, THD1, to continue. It will enter the mutex --echo ** lock and set query cache status to TABLE_FLUSH_IN_PROGRESS and then --echo ** unlock the mutex before stopping on the next debug hook. SELECT SQL_NO_CACHE id FROM information_schema.processlist WHERE state='wait_in_query_cache_invalidate1' LIMIT 1 INTO @flush_thread_id; KILL QUERY @flush_thread_id; --echo ** Assert that we reach the next debug hook. LET $wait_condition= SELECT SQL_NO_CACHE COUNT(*)= 1 FROM information_schema.processlist WHERE state='wait_in_query_cache_invalidate2'; --source include/wait_condition.inc --echo ** --echo ** Signal the remaining debug hooks blocking THD2 and THD3. --echo ** The threads will grab the guard mutex enter the wait condition and --echo ** and finally release the mutex. The threads will continue to wait --echo ** until a broadcast signal reaches them causing both threads to --echo ** come alive and check the condition. SELECT SQL_NO_CACHE id FROM information_schema.processlist WHERE state='wait_in_query_cache_insert' ORDER BY id ASC LIMIT 1 INTO @thread_id; KILL QUERY @thread_id; SELECT SQL_NO_CACHE id FROM information_schema.processlist WHERE state='wait_in_query_cache_insert' ORDER BY id DESC LIMIT 1 INTO @thread_id; KILL QUERY @thread_id; --echo ** --echo ** Finally signal the DELETE statement on THD1 one last time. --echo ** The stmt will complete the query cache invalidation and return --echo ** cache status to NO_FLUSH_IN_PROGRESS. On the status change --echo ** One signal will be sent to the thread group waiting for executing --echo ** invalidations and a broadcast signal will be sent to the thread --echo ** group holding result set writers. SELECT SQL_NO_CACHE id FROM information_schema.processlist WHERE state='wait_in_query_cache_invalidate2' LIMIT 1 INTO @flush_thread_id; KILL QUERY @flush_thread_id; --echo ** --echo ************************************************************************* --echo ** No tables should be locked connection thd2; --echo =================================== Connection thd2 reap; DELETE FROM t1; DELETE FROM t2; DELETE FROM t3; connection thd3; --echo =================================== Connection thd3 reap; DELETE FROM t4; DELETE FROM t5; connection thd1; --echo =================================== Connection thd1 reap; --echo ** Done. connection default; disconnect thd1; disconnect thd2; disconnect thd3; SET GLOBAL query_cache_size= 0; connection default; --echo # Restore defaults RESET QUERY CACHE; FLUSH STATUS; DROP TABLE t1,t2,t3,t4,t5; SET GLOBAL query_cache_size= DEFAULT; SET GLOBAL query_cache_type= DEFAULT; exit;