crashes (sig 11) with 5.3.7-MariaDB union query
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
MariaDB |
New
|
Undecided
|
Unassigned |
Bug Description
Hello and thanks for mariadb-
Running on 2.6.18-274.7.1.el5 x86_64 x86_64 x86_64 GNU/Linux RedHat EL.
We recently upgraded some mysqld instances in a pool from MySQL 5.1.X to mariadb 5.3.7, we have had two crashes (on different instances on different hosts) with the same backtrace and very similar queries, the pool is a production pool so the priority has been restoration of service and a rollback, the query from the first backtrace did not cause a crash when run in isolation on our development and staging instances (I have not tested the 2nd yet), the development and staging instances do not have identical configurations, data or queries running, but are the same version (MariaDB 5.3.7) on the same OS on the same architecture. Oh, also both mariadb instances ran for several days days in production before crashing.
Here are the contents of the error log for the first crash (the backtrace is the same for the second crash and the query is very similar). I have removed the actual query reported and have included a representation of the query, I can send the actual query and table definitions privately.
I am wondering if (and hoping that) the backtrace looks familiar.
120627 5:20:14 [ERROR] mysqld got signal 11 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
To report this bug, see http://
We will try our best to scrape up some info that will hopefully help
diagnose the problem, but since we have already crashed,
something is definitely wrong and this may fail.
Server version: 5.3.7-MariaDB-log
key_buffer_
read_buffer_
max_used_
max_threads=3001
thread_count=29
connection_count=29
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_
Hope that's ok; if not, decrease some variables in the equation.
Thread pointer: 0x0x2ab7fc3499b0
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 0x512fc0f8 thread_stack 0x48000
./bin/mysqld(
./bin/mysqld(
/lib64/
./bin/mysqld [0x6be068]
./bin/mysqld(
./bin/mysqld(
./bin/mysqld(
./bin/mysqld(
./bin/mysqld [0x647e7e]
./bin/mysqld(
./bin/mysqld(
./bin/mysqld(
./bin/mysqld(
./bin/mysqld(
/lib64/
/lib64/
Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (0x2ab7deb1abf8):
(select many fields from a few tables with joins and inner joins group by sort by limit 5000)
UNION ALL
(select many fields from a few tables with joins and inner joins group by sort by limit 5000)
order by limit 5000
Connection ID (thread ID): 30483258
Status: KILL_CONNECTION
Optimizer switch: index_merge=
Thank you.
Hi Peter,
According to the log, the connection is in KILL_CONNECTION status -- were you trying to kill it because it was hung?
If so, it somewhat reminds the bug #998516 (don't be fooled by the 'released' status, it was fixed after 5.3.7).
Otherwise, there is not much of a stack trace, but I will see what else we had with UNION recently.