BUF_LRU_MIN_LEN (256) is too high value for low buffer pool(BP) size.
For example, for BP size lower than 80M and 16 K page size, the limit is
more than 5% of total BP and for lowest BP 5M, it is 80% of the BP.
Non-data objects like explicit locks could occupy part of the BP pool
reducing the pages available for LRU. If LRU reaches minimum limit and
if no free pages are available, server would hang with page cleaner not
able to free any more pages.
Fix: To avoid such hang, we adjust the LRU limit lower than the limit
for data objects as checked in buf_LRU_check_size_of_non_data_objects()
i.e. one page less than 5% of BP.
trx_free_at_shutdown(): Similar to trx_t::commit_in_memory(),
clear the detailed_error (FOREIGN KEY constraint error) before
invoking trx_t::free(). We only do this on debug instrumented
builds in order to avoid a debug assertion failure on shutdown.
A wide_handler is shared among ha_spider of partitions of the same
spider table, where the last partition is designated the owner of the
wide_handler, and is responsible for its deallocation. Therefore in
case of failure, we only reset wide_handler in error handling if the
current ha_spider is the owner of the wide_handler, otherwise it will
result in segv in the destructor of ha_spider, or during
ha_spider::close().
The init, init_error, and init_error_time fields of a SPIDER_SHARE
should only be assigned when actually doing the initialisation of a
SPIDER_SHARE, otherwise they could result in spurious failures from
spider_get_share() in a subsequent statement.
Similar to #2480.
567b681 introduced safe_strcpy() to minimize the use of C with
potentially unsafe memory overflow with strcpy() whose use is
discouraged.
Replace instances of strcpy() with safe_strcpy() where possible, limited
here to files in the `sql/` directory.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer
Amazon Web Services, Inc.
Spider calls info with HA_STATUS_AUTO to update auto increment info,
which may attempt to connect the data node. If the connection fails,
it may emit an error and return the same error. This error should not
be of lower priority than any possible error from the later call to
handler::update_auto_increment().
Without this change, certain errors from update_auto_increment() such
as HA_ERR_AUTOINC_ERANGE may get ignored, causing my_insert() to call
my_ok(), which fails the assertion because the error was emitted in
the info() call (Diagnostics_area::is_set() returns true).
The accounting of the limit variable that represents the
amount of space left it the buffer was incorrect.
Also there was 1 or 2 bytes left to write that occured without
the buffer length being checked.
Review: Sanja Byelkin
MariaDB-backup needs to check for SLAVE MONITOR as that is
what is returned by SHOW GRANTS.
Update test to ensure that warnings about missing privileges
do not occur when the backup is successful.
Reviewer: Andrew Hutchings
Thanks Eugene for reporting the issue.
Workaround patch: Do not remove GROUP BY clause when it has
subquer(ies) in it.
remove_redundant_subquery_clauses() removes redundant GROUP BY clause
from queries in form:
expr IN (SELECT no_aggregates GROUP BY ...)
expr {CMP} {ALL|ANY|SOME} (SELECT no_aggregates GROUP BY ...)
This hits problems when the GROUP BY clause itself has subquer(y/ies).
This patch is just a workaround: it disables removal of GROUP BY clause
if the clause has one or more subqueries in it.
Tests:
- subselect_elimination.test has all known crashing cases.
- subselect4.result, insert_select.result are updated.
Note that in some cases results of SELECT are changed too (not just
EXPLAINs). These are caused by non-deterministic SQL: when running a
query like:
x > ANY( SELECT col1 FROM t1 GROUP BY constant_expression)
without removing the GROUP BY, the executor is free to pick the value
of t1.col1 from any row in the GROUP BY group (denote it $COL1_VAL).
Then, it computes x > ANY(SELECT $COL1_VAL).
When running the same query and removing the GROUP BY:
x > ANY( SELECT col1 FROM t1)
the executor will actually check all rows of t1.
The problem was two fold:
- REPAIR TABLE t1 USE_FRM did not work for transactional
Aria tables (Table was thought to be repaired, which it was not) which
caused issues in later usage of the table.
- When swapping tmp_data file to data file, sort_info files where not
updated. This caused problems if there was several unique keys and
there was a duplicate for the second key.
Due to this bug a wrong result might be expected from queries with
an IN subquery predicate in the WHERE clause and a derived table in the
FROM clause to which split optimization could be applied.
The function JOIN::fix_all_splittings_in_plan() used the value of the
bitmap JOIN::sjm_lookup_tables() such as it had been left after the
search for the best plan for the select containing the splittable
derived table. That value could not be guaranteed to be correct. So the
recalculation of this bitmap is needed to exclude the plans with key
accesses from SJM lookup tables.
Approved by Igor Babaev <igor@maridb.com>
safety first - tell mariadb client not to execute dangerous
cli commands, they cannot be present in the dump anyway.
wrapping the command in /*!999999 ..... */ guarantees that
if a non-mariadb-cli client loads the dump and sends it to the
server - the server will ignore the command it doesn't understand
mysql --sandbox
disables system (\!), tee (\T), pager with an argument(\P foo), source (\.)
does *not* disable edit (\e). Use EDITOR=/bin/false to disable
or, for example, EDITOR=rnano for something more useful
does *not* disable pager (\P) without an argument. Use
PAGER=cat or, for example PAGER=less LESSSECURE=1 for something
more useful
using a disabled command is an error, which can be ignored with --force
Also, a "sandbox" command (\-) - enables the sandbox mode until EOF
(current file or the session, if interactive)
on disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE) the engine does
not know that the long unique is logically unique, because on the
engine level it is not. And the engine disables it,
Change the disable_indexes/enable_indexes API. Instead of the enum
mode, send a key_map of indexes that should be enabled. This way the
server will decide what is unique, not the engine.
This commit fixes sporadic failures in galera_3nodes_sr.GCF-336
test. The following changes have been made here:
1) A small addition to the test itself which should make
it more deterministic by waiting for non-primary state
before COMMIT;
2) More careful handling of the wsrep_ready variable in
the server code (it should always be protected with mutex).
No additional tests are required.
dgcov.pl was putting gcov execution counters on wrong lines
in the report (*.dgcov files were correct), because it was
incrementing the new line number for diff lines starting from '-'
(lines from the old file, not present in the new)
