The problem was in a test case for Bug33507:
- when the number of active connections reaches the limit,
the server accepts only root connections. That's achieved by
accepting a connection, negotiating with the client and
checking user credentials. If it is not SUPER, the connection
is dropped.
- when the server accepts connection, it increases the counter;
- when the server drops connection, it decreases the counter;
- the race was in between of decreasing the counter and accepting
new connection:
- max_user_connections = 2;
- 2 oridinary user connections accepted;
- extra user connection is establishing;
- server checked user credentials, and sent 'Too many connections'
error;
- the client receives the error and establishes extra SUPER user
connection;
- the server however didn't decrease the counter (the extra
user connection still is "alive" in the server) -- so, the new
SUPER-user connection, will be dropped, because it exceeds
(max_user_connections + 1).
The fix is to implement "safe connect", which makes several attempts
to connect and use it in the test script.
in some case.
ER_CON_COUNT_ERROR is defined with SQL state 08004. However, this SQL state is not always
returned.
This error can be thrown in two cases:
1. when an ordinary user (a user w/o SUPER privilege) is connecting,
and the number of active user connections is equal or greater than
max_connections.
2. when a user is connecting and the number of active user connections is
already (max_connections + 1) -- that means that no more connections will
be accepted regardless of the user credentials.
In the 1-st case, SQL state is correct.
The bug happens in the 2-nd case -- on UNIX the client gets 00000 SQL state, which is
absolutely wrong (00000 means "not error SQL state); on Windows
the client accidentally gets HY000 (which means "unknown SQL state).
The cause of the problem is that the server rejects extra connection
prior to read a packet with client capabilities. Thus, the server
does not know if the client supports SQL states or not (if the client
supports 4.1 protocol or not). So, the server supposes the worst and
does not send SQL state at all.
The difference in behavior on UNIX and Windows occurs because on Windows
CLI_MYSQL_REAL_CONNECT() invokes create_shared_memory(), which returns
an error (in default configuration, where shared memory is not configured).
Then, the client does not reset this error, so when the connection is
rejected, SQL state is HY000 (from the error from create_shared_memory()).
The bug appeared after test case for Bug#33507 -- before that, this behavior
just had not been tested.
The fix is to 1) reset the error after create_shared_memory();
2) set SQL state to 'unknown error' if it was not received from
the server.
A separate test case is not required, since the behavior is already
tested in connect.test.
Note for doc-team: the manual should be updated to say that under
some circumstances, 'Too many connections' has HY000 SQL state.
than max_connections -- which results in user lockout.
The problem was that the variable thread_count that contains
the number of active threads was interpreted as a number of
active connections.
The fix is to introduce a new counter for active connections.
Post-commit issues fixed
* Test results for other tests fixed due to added error #s
* Memory allocation/free issues found with running with valgrind
* Fix to mysql-test-run shell script to run federated_server test (installs
mysql.servers table properly)
Moved .progress files into the log directory
Moved 'cluster' database tables into the MySQL database, to not have 'cluster' beeing a reserved database name
Fixed bug where mysqld got a core dump when trying to use a table created by MySQL 3.23
Fixed some compiler warnings
Fixed small memory leak in libmysql
Note that this doesn't changeset doesn't include the new mysqldump.c code required to run some tests. This will be added when I merge 5.0 to 5.1
- fixed test results
- fixed bug caught by information_schema.test . Bison temporal
variables are very nice but extremely error-prone (Count one more
time just to be sure).
Added basic per-thread time zone functionality (based on public
domain elsie-code). Now user can select current time zone
(from the list of time zones described in system tables).
All NOW-like functions honor this time zone, values of TIMESTAMP
type are interpreted as values in this time zone, so now
our TIMESTAMP type behaves similar to Oracle's TIMESTAMP WITH
LOCAL TIME ZONE (or proper PostgresSQL type).
WL#1266 "CONVERT_TZ() - basic time with time zone conversion
function".
Fixed problems described in Bug #2336 (Different number of warnings
when inserting bad datetime as string or as number). This required
reworking of datetime realted warning hadling (they now generated
at Field object level not in conversion functions).
Optimization: Now Field class descendants use table->in_use member
instead of current_thd macro.
--old-passwords
Support for option --old-protocol was removed.
Some test performed.
Tests for SSL and replication are pending.
More strict following to specification for --old-passwords
is in the TODO.
Portability fixes
Added new client function: mysql_get_server_version()
New server help code (From Victor Vagin)
Fixed wrong usage of binary()
Disabled RTREE usage for now.
