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.
with gcc 4.3.2
This patch fixes a number of GCC warnings about variables used
before initialized. A new macro UNINIT_VAR() is introduced for
use in the variable declaration, and LINT_INIT() usage will be
gradually deprecated. (A workaround is used for g++, pending a
patch for a g++ bug.)
GCC warnings for unused results (attribute warn_unused_result)
for a number of system calls (present at least in later
Ubuntus, where the usual void cast trick doesn't work) are
also fixed.
unnecessarily
The problem is that libmysqlclient.so is built with THREAD
undefined, while a client compiling against the same header
files will see THREAD as defined and definitions in
my_pthread.h will be included, possibly resulting in undefined
symbols that cannot be resolved with libmysqlclient.so.
The suggested solution is to require that clients wanting to
link with libmysqlclient.so should be built with
MYSQL_CLIENT_NO_THREADS defined. This requires a documentation
change, and more details for this will be supplied if this
patch is approved.
The MYSQL_CLIENT_NO_THREADS define was renamed from
UNDEF_THREADS_HACK, to get a more suitable (less suspicious)
name for the define. (The UNDEF_THREADS_HACK is retained for
backwards compatibility, though.)
This patch is also in anticipation of WL#4958, which will
remove this problem altogether by dropping the building of
libmysqlclient.
Bug#34309: '_PC' macro redefinition
For reasons that are now a mystery, we had defined a CPP symbol to
help ancient compilers work better (in some way that's lost to history).
This interferes with at least one modern compiler.
Now, don't define the _PC symbol. Those other underscore-leading
symbols are suspect also, but at least the names aren't inscrutable.
Let's leave them for now.
produce incorrect results for ROUND()
Added a workaround and a configure check to test whether
isinf() is affected by the GCC bug #39228.
Since no code in MySQL server is currently affected by that
bug, the patch is actually a safeguard for possible future
code modifications. No test cases or changelog entries are
needed.
- Header <sys/ttydefaults.h> missing or not usable on QNX and OpenServer 6
include/my_global.h
- Moved down definition of function rint(), as for some platforms (in
this case Netware) 'longlong' is not defined until later in
"my_global.h"
for bug #15936.
On some platforms fenv.h may #undef the min/max macros
defined in my_global.h.
Fixed by moving the #include directive for fenv.h from
mysqld.cc to my_global.h before definitions for min/max.
Both of our own implementations of rint(3) were inconsistent with the
most common behavior of rint() on those platforms that have it: round
to nearest, break ties by rounding to nearest even.
Fixed by leaving just one implementation of rint() in our source tree,
and changing its behavior to match the most common native
implementations on other platforms.
code backported from 6.0
per-file messages:
include/my_global.h
Remove SC_MAXWIDTH. This is unused and irrelevant nowadays.
include/my_sys.h
Remove errbuf declaration and unused definitions.
mysys/my_error.c
Remove errbuf definition and move and adjust ERRMSGSIZE.
mysys/my_init.c
Declare buffer on the stack and use my_snprintf.
mysys/safemalloc.c
Use size explicitly. It's more than enough for the message at hand.
sql/sql_error.cc
Use size explicitly. It's more than enough for the message at hand.
sql/sql_parse.cc
Declare buffer on the stack. Use my_snprintf as it will result in
less stack space being used than by a system provided sprintf --
this allows us to put the buffer on the stack without causing much
trouble. Also, the use of errbuff here was not thread-safe as the
function can be entered concurrently from multiple threads.
sql/sql_table.cc
Use MYSQL_ERRMSG_SIZE. Extra space is not needed as my_snprintf will
nul terminate strings.
storage/myisam/ha_myisam.cc
Use MYSQL_ERRMSG_SIZE.
sql/share/errmsg.txt
Error message truncation in test "innodb" in embedded mode
filename in the error message can safely take up to 210 symbols.
For reasons that are now a mystery, we had defined a CPP symbol to
help ancient compilers work better (in some way that's lost to history).
This interferes with at least one modern compiler.
Now, don't define the _PC symbol. Those other underscore-leading
symbols are suspect also, but at least the names aren't inscrutable.
Let's leave them for now.
conflicts:
Text conflict in client/mysqltest.cc
Text conflict in mysql-test/include/wait_until_connected_again.inc
Text conflict in mysql-test/lib/mtr_report.pm
Text conflict in mysql-test/mysql-test-run.pl
Text conflict in mysql-test/r/events_bugs.result
Text conflict in mysql-test/r/log_state.result
Text conflict in mysql-test/r/myisam_data_pointer_size_func.result
Text conflict in mysql-test/r/mysqlcheck.result
Text conflict in mysql-test/r/query_cache.result
Text conflict in mysql-test/r/status.result
Text conflict in mysql-test/suite/binlog/r/binlog_index.result
Text conflict in mysql-test/suite/binlog/r/binlog_innodb.result
Text conflict in mysql-test/suite/rpl/r/rpl_packet.result
Text conflict in mysql-test/suite/rpl/t/rpl_packet.test
Text conflict in mysql-test/t/disabled.def
Text conflict in mysql-test/t/events_bugs.test
Text conflict in mysql-test/t/log_state.test
Text conflict in mysql-test/t/myisam_data_pointer_size_func.test
Text conflict in mysql-test/t/mysqlcheck.test
Text conflict in mysql-test/t/query_cache.test
Text conflict in mysql-test/t/rpl_init_slave_func.test
Text conflict in mysql-test/t/status.test
bigint' fails on windows.
Visual Studio does not take into account some x86 hardware limitations
which leads to incorrect results when converting large DOUBLE values
to BIGINT UNSIGNED ones.
Fixed by adding a workaround for double->ulonglong conversion on
Windows.
WL#4165 Prepared statements: validation
WL#4166 Prepared statements: automatic re-prepare
Fixes
Bug#27430 Crash in subquery code when in PS and table DDL changed after PREPARE
Bug#27690 Re-execution of prepared statement after table was replaced with a view crashes
Bug#27420 A combination of PS and view operations cause error + assertion on shutdown
The basic idea of the patch is to keep track of table metadata between
prepared statement prepare and execute. If some table used in the statement
has changed, the prepared statement is re-prepared before execution.
See WL#4165 and WL#4166 contents and comments in the code for details
of the implementation.
The bool data type was redefined to BOOL (4 bytes on windows).
Removed the #define and fixed some of the warnings that were uncovered
by this.
Note that the fix also disables 2 warnings :
4800 : 'type' : forcing value to bool 'true' or 'false' (performance warning)
4805: 'operation' : unsafe mix of type 'type' and type 'type' in operation
These warnings will be handled in a separate bug, as they are performance related or bogus.
Fixed to int the return type of functions that return more than
2 distinct values.
floating point numbers
Some math functions did not check if the result is a valid number
(i.e. neither of +-inf or nan).
Fixed by validating the result where necessary and returning NULL in
case of invalid result.
value" error even though the value was correct): a C function in my_getopt.c
was taking bool* in parameter and was called from C++ sql_plugin.cc,
but on some Mac OS X sizeof(bool) is 1 in C and 4 in C++, giving funny
mismatches. Fixed, all other occurences of bool in C are removed, future
ones are blocked by a "C-bool-catcher" in my_global.h (use my_bool).
