The test allowed random coincidence of connection ids for two concurrent
sessions performing CREATE/DROP temp tables.
Fixed with correcting the test. The sessions connection ids are not changed
from their defaults anymore.
When compressed myisam files are opened, they are always memory mapped
sometimes causing memory swapping problems.
When we mmap the myisam compressed tables of size greater than the memory
available, the kswapd0 process utilization is very high consuming 30-40% of
the cpu. This happens only with linux kernels older than 2.6.9
With newer linux kernels, we don't have this problem of high cpu consumption
and this option may not be required.
The option 'myisam_mmap_size' is added to limit the amount of memory used for
memory mapping of myisam files. This option is not dynamic.
The default value on 32 bit system is 4294967295 bytes and on 64 bit system it
is 18446744073709547520 bytes.
Note: Testcase only tests the option variable. The actual bug has be to
tested manually.
returns incorrect results with where
An outer join of a const table (outer) and a normal table
(inner) with GROUP BY on a field from the outer table would
optimize away GROUP BY, and thus trigger the optimization to
do away with a temporary table if grouping was performed on
columns from the const table, hence executing the query with
filesort without temporary table. But this should not be
done if there is a non-indexed access to the inner table,
since filesort does not handle joins. It expects either ref
access, range ditto or table scan. The join condition will
thus not be applied.
Fixed by always forcing execution with temporary table in
the case of ROLLUP with a query involving an outer join. This
is a slightly broader class of queries than need fixing, but
it is hard to ascertain the position of a ROLLUP field wrt
outer join with current query representation.
Problem: inserting a record we don't set unused null bits in the
record buffer if no default field values used.
That may lead to wrong live checksum calculation.
Fix: set unused null bits in the record buffer in such cases.
The bug is caused by a race condition between the
INSERT DELAYED thread and the client thread's FLUSH TABLE. The
FLUSH TABLE does not guarantee (as is (wrongly) suggested in the
test case) that the INSERT DELAYED is ever executed. The
execution of the test case will thus not be deterministic.
The fix has been to do a deterministic verification that both
threads are complete by checking the content of the table.
This test case tests a circular replication of four hosts.
A--->B--->C--->D--->A
The replicate is slow and needs more time to replicate all data in the circle.
The time it spends to replicate, sometimes, is longer than the time that
wait_condition.inc spends to wait that all data has been replicated. This
cause sporadical failure of this test case.
This patch uses sync_slave_with_master to ensure that all data can be replicated
successfully in the circle.
from mysql-next-mr-bugfixing to mysql-trunk-bugfixing.
Original revision:
------------------------------------------------------------
revision-id: zhenxing.he@sun.com-20091127084945-wng7gakygduv3q8k
committer: He Zhenxing <zhenxing.he@sun.com>
branch nick: 5.1-rep-semisync
timestamp: Fri 2009-11-27 16:49:45 +0800
message:
Bug#48351 Inconsistent library names for semisync plugin
The semisync plugin library names on Unix like systems were prefixed with
'lib', which did not follow the conventions.
Fix the problem by removing the 'lib' prefix on Unix systems.
------------------------------------------------------------
plugin prevents it from getting tested) from mysql-next-mr-bugfixing
to mysql-trunk-bugfixing.
Original revision:
------------------------------------------------------------
revision-id: zhenxing.he@sun.com-20091204014339-2m06r42vajhm9vke
committer: He Zhenxing <zhenxing.he@sun.com>
branch nick: 5.1-rep-semisync
timestamp: Fri 2009-12-04 09:43:39 +0800
message:
Bug#49170 Inconsistent placement of semisync plugin prevents it from getting tested
Add $basedir/lib/plugin to the search paths for semisync plugins.
------------------------------------------------------------
from mysql-next-mr-bugfixing into mysql-trunk-bugfixing.
NOTE: the "utf8_phone_ci" collation does not exist in mysql-trunk yet,
so another collation with 2-byte collation ID is used: "utf8_test_ci".
This patch will be null-merged to mysql-next-mr-bugfixing.
Original revision:
------------------------------------------------------------
revision-id: bar@mysql.com-20091207121153-hs3bqbmr0719ws21
committer: Alexander Barkov <bar@mysql.com>
branch nick: mysql-next-mr.b47756
timestamp: Mon 2009-12-07 16:11:53 +0400
message:
Bug#47756 Setting 2byte collation ID with 'set names' crashes the server
The problem is not actually related to 2byte collation IDs.
The same crash happens if you change the collation ID in
mysql-test/str_data/Index.xml to a value smaller than 256.
Crash happened in SQL parser, because the "ident_map" and "state_map"
arrays were not initialized in loadable utf8 collations.
Fix: adding proper initialization of the "ident_map" and "state_map"
members for loadable utf8 collations.
------------------------------------------------------------
int join_read_key(JOIN_TAB*)
The eq_ref access method TABLE_REF (accessed through
JOIN_TAB) to save state and to track if this is the
first row it finds or not.
This state was not reset on subquery re-execution
causing an assert.
Fixed by resetting the state before the subquery
re-execution.
NULLable BIGINT and INT columns in comparison
Problem: a consequence of the fix for 43668.
Some Arg_comparator inner initialization missed,
that may lead to unpredictable (wrong) comparison
results.
Fix: always properly initialize Arg_comparator
before its usage.
for InnoDB
The class Field_bit_as_char stores the metadata for the
field incorrecly because bytes_in_rec and bit_len are set
to (field_length + 7 ) / 8 and 0 respectively, while
Field_bit has the correct values field_length / 8 and
field_length % 8.
Solved the problem by re-computing the values for the
metadata based on the field_length instead of using the
bytes_in_rec and bit_len variables.
To handle compatibility with old server, a table map
flag was added to indicate that the bit computation is
exact. If the flag is clear, the slave computes the
number of bytes required to store the bit field and
compares that instead, effectively allowing replication
*without conversion* from any field length that require
the same number of bytes to store.
This deadlock would occur between two connections A and B if statements
where executed in the following way:
1) Connection A executes a DML statement against table s1.t1 with
autocommit off. This causes a shared metadata lock on s1.t1 to be
acquired. (With autocommit on, the metadata lock will be dropped once
the statment completes and the deadlock will not occour.)
2) Connection B tries to DROP DATABASE s1. This will block against the
metadata lock connection A holds on s1.t1. While blocking, connection B
will hold the LOCK_mysql_create_db mutex.
3) Connection A tries to ALTER DATABASE s1. This will block when trying
to get LOCK_mysql_create_db mutex held by connection B.
4) Deadlock between DROP DATABASE and ALTER DATABASE (which has autocommit
off).
If Connection A used an explicitly started transaction rather than having
autocommit off, this deadlock did not happen as ALTER DATABASE is
disallowed inside transactions.
This patch fixes the problem by changing ALTER DATABASE to cause an
implicit commit before executing. This will cause the metadata
lock on s1.t1 to be dropped, allowing DROP DATABASE to proceed.
This will in turn cause the LOCK_mysql_create_db mutex to be unlocked,
allowing ALTER DATABASE to proceed.
Note that SQL commands other than ALTER DATABASE that also use
LOCK_mysql_create_db, already cause an implicit commit.
Incompatible change: ALTER DATABASE (and its synonym ALTER SCHEMA)
now cause an implicit commit. This must be reflected in the
documentation.
Test case added to schema.test.
int join_read_key(JOIN_TAB*)
The eq_ref access method TABLE_REF (accessed through
JOIN_TAB) to save state and to track if this is the
first row it finds or not.
This state was not reset on subquery re-execution
causing an assert.
Fixed by resetting the state before the subquery
re-execution.
Problem: add_collation did not check that cs->number is smaller
than the number of elements in the array all_charsets[],
so server could crash when loading an Index.xml file with
a collation ID greater the number of elements
(for example when downgrading from 5.5).
Fix: adding a condition to check that cs->number is not out of valid range.
