data dictionary confusion
On file systems with case insensitive file names, and
lower_case_table_names set to '2', the server could crash
due to a table definition cache inconsistency. This is
the default setting on MacOSX, but may also be set and
used on MS Windows.
The bug is caused by using two different strategies for
creating the hash key for the table definition cache, resulting
in failure to look up an entry which is present in the cache,
or failure to delete an existing entry. One strategy was to
use the real table name (with case preserved), and the other
to use a normalized table name (i.e a lower case version).
This is manifested in two cases. One is during 'DROP DATABASE',
where all known files are removed. The removal from
the table definition cache is done via a generated list of
TABLE_LIST with keys (wrongly) created using the case preserved
name. The other is during CREATE TABLE, where the cache lookup
is also (wrongly) based on the case preserved name.
The fix was to use only the normalized table name when
creating hash keys.
(variables_debug fails)
The problem was that "SET GLOBAL debug" could cause a crash on Solaris.
The crash happened if the server failed to open the trace file given in
the "SET GLOBAL debug" statement. This caused an error message to be
printed to stderr containing the process name. However, printing to
stderr crashed the server since the pointer to the process name had
not been initialized.
This patch fixes the problem by initializing the process name
properly when doing "SET GLOBAL debug".
No test case added as this bug was repeatable with existing test
coverage in variables_debug.test.
After the fix for
Bug #55077 Assertion failed: width > 0 && to != ((void *)0), file .\dtoa.c
we no longer try to allocate a string of length 'field_length'
so the asserts are relevant only for ZEROFILL columns.
Enable the MySQL maintainer-specific development environment
(which add various warning related options to the compiler
flags) if debugging support is enabled.
For crash testing: kill the server without generating core file.
include/my_dbug.h
Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
Kill server without generating core.
sql/log.cc
Kill server without generating core.
For crash testing: kill the server without generating core file.
include/my_dbug.h
Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
Kill server without generating core.
sql/log.cc
Kill server without generating core.
replication aborts
When recieving a 'SLAVE STOP' command, slave SQL thread will roll back the
transaction and stop immidiately if there is only transactional table updated,
even through 'CREATE|DROP TEMPOARY TABLE' statement are in it. But These
statements can never be rolled back. Because the temporary tables to the user
session mapping remain until 'RESET SLAVE', Therefore it will abort SQL thread
with an error that the table already exists or doesn't exist, when it restarts
and executes the whole transaction again.
After this patch, SQL thread always waits till the transaction ends and then stops,
if 'CREATE|DROP TEMPOARY TABLE' statement are in it.
The thing is that the following attributes are fixed (remembered) when a trigger
is created:
- character_set_client
- character_set_results
- collation_connection
There are two triggers created in mysql-test/include/mtr_warnings.sql.
They were created using "current default" character set / collation.
is_triggers.test shows definition of these triggers including recorded
character set information.
The problem was that if "current default" changed, the recorded character
set information was not accurate.
There might be two ways to fix that:
a) update is_triggers.test so that it does not put character-set information
into result-file;
b) update mtr_warnings.sql so that the triggers are created using
hard-coded character sets.
This patch implements option b).
The root of the problem is that to interrupt a slave SQL thread
wait, the STOP SLAVE implementation uses thd->awake(THD::NOT_KILLED).
This appears as a spurious wakeup (e.g. from a sleep on a
condition variable) to the code that the slave SQL thread is
executing at the time of the STOP. If the code is not written
to be spurious-wakeup safe, unexpected behavior can occur. For
the reported case, this problem led to an infinite loop around
the interruptible_wait() function in item_func.cc (SLEEP()
function implementation). The loop was not being properly
restarted and, consequently, would not come to an end. Since the
SLEEP function sleeps on a timed event in order to be killable
and to perform periodic checks until the requested time has
elapsed, the spurious wake up was causing the requested sleep
time to be reset every two seconds.
The solution is to calculate the requested absolute time only
once and to ensure that the thread only sleeps until this
time is elapsed. In case of a spurious wake up, the sleep is
restarted using the previously calculated absolute time. This
restores the behavior present in previous releases. If a slave
thread is executing a SLEEP function, a STOP SLAVE statement
will wait until the time requested in the sleep function
has elapsed.
for --init-rpl-role.
Problem: There are two variables involved in this issue,
rpl_status and rpl_role_type. The former is an array containing
the description of the possible values for the latter.
rpl_status is declared as an enumeration and is stored in a 4
bytes integer. On the other hand, my_getopt, reads enum values
into a ulong:
*(ulong*)value= arg;
This is overwriting the memory used for rpl_role_type,
corrupting the first entry in the array.
Fix: We fix this by re-declaring rpl_status as a ulong, so that it
has space to accommodate the value "parsed" in my_getopt .
After ALTER TABLE which changed only table's metadata, row-based
binlog sometimes got corrupted since the tablemap was unexpectedly
set to 0 for subsequent updates to the same table.
ALTER TABLE which changed only table's metadata always reset
table_map_id for the table share to 0. Despite the fact that
0 is a valid value for table_map_id, this step caused problems
as it could have created situation in which we had more than
one table share with table_map_id equal 0. If more than one
table with table_map_id are 0 were updated in the same statement,
updates to these different tables were written into the same
rows event. This caused slave server to crash.
This bug happens only on 5.1. It doesn't affect 5.5+.
This patch solves this problem by ensuring that ALTER TABLE
statements which change metadata only never reset table_map_id
to 0. To do this it changes reopen_table() to correctly use
refreshed table_map_id value instead of using the old one/
resetting it.
When slave executes a transaction bigger than slave's max_binlog_cache_size,
slave will crash. It is caused by the assert that server should only roll back
the statement but not the whole transaction if the error ER_TRANS_CACHE_FULL
happens. But slave sql thread always rollbacks the whole transaction when
an error happens.
Ather this patch, we always clear any error set in sql thread(it is different
from the error in 'SHOW SLAVE STATUS') and it is cleared before rolling back
the transaction.
Bug#55744 GROUP_CONCAT + CASE + ucs return garbage
revealed problems in how character set aggregation
code works with prepared statements.
This patch fixes (hopefully) the problems.
