MDEV-33502 Slowdown when running nested statement with many partitions
This change was triggered to help some MariaDB users with close to
10000 bits in their bitmaps.
- Change underlaying storage to be 64 bit instead of 32bit.
- This reduses number of loops to scan bitmaps.
- This can cause some bitmaps to be 4 byte large.
- Ensure that all not used top-bits are always 0 (simplifes code as
the last 64 bit storage is not a special case anymore).
- Use my_find_first_bit() to find the first set bit which is much faster
than scanning trough things byte by byte and then bit by bit.
Other things:
- Added a bool to remember if my_bitmap_init() did allocate the bitmap
array. my_bitmap_free() will only free arrays it did allocate.
This allowed me to remove setting 'bitmap=0' before calling
my_bitmap_free() for cases where the bitmap's where allocated externally.
- my_bitmap_init() sets bitmap to 0 in case of failure.
- Added 'universal' asserts to most bitmap functions.
- Change all remaining calls to bitmap_init() to my_bitmap_init().
- To finish the change from 2014.
- Changed all usage of uint32 in my_bitmap.h to my_bitmap_map.
- Updated bitmap_copy() to handle bitmaps of different size.
- Removed const from bitmap_exists_intersection() as this caused casts
on all usage.
- Removed not used function bitmap_set_above().
- Renamed create_last_word_mask() to create_last_bit_mask() (to match
name changes in my_bitmap.cc)
- Extended bitmap-t with test for more bitmap functions.
The patch for "MDEV-25440: Indexed CHAR ... broken with NO_PAD collations"
fixed these scenarios from MDEV-26743:
- Basic latin letter vs equal accented letter
- Two letters vs equal (but space padded) expansion
However, this scenario was still broken:
- Basic latin letter (but followed by an ignorable character)
vs equal accented letter
Fix:
When processing for a NOPAD collation a string with trailing ignorable
characters, like:
'<non-ignorable><ignorable><ignorable>'
the string gets virtually converted to:
'<non-ignorable><ignorable><ignorable><space><space><space>...'
After the fix the code works differently in these two cases:
1. <space> fits into the "nchars" limit
2. <space> does not fit into the "nchars" limit
Details:
1. If "nchars" is large enough (4+ in this example),
return weights as follows:
'[weight-for-non-ignorable, 1 char] [weight-for-space-character, 3 chars]'
i.e. the weight for the virtual trailing space character now indicates
that it corresponds to total 3 characters:
- two ignorable characters
- one virtual trailing space character
2. If "nchars" is small (3), then the virtual trailing space character
does not fit into the "nchar" limit, so return 0x00 as weight, e.g.:
'[weight-for-non-ignorable, 1 char] [0x00, 2 chars]'
Adding corresponding MTR tests and unit tests.
Checking for kill with thd_kill_level() or check_killed() runs apc
requests, which takes the LOCK_thd_kill mutex. But this is dangerous,
as checking for kill needs to be called while holding many different
mutexes, and can lead to cyclic mutex dependency and deadlock.
But running apc is only "best effort", so skip running the apc if the
LOCK_thd_kill is not available. The apc will then be run on next check
of kill signal.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
- Adding a new argument "flag" to MY_COLLATION_HANDLER::strnncollsp_nchars()
and a flag MY_STRNNCOLLSP_NCHARS_EMULATE_TRIMMED_TRAILING_SPACES.
The flag defines if strnncollsp_nchars() should emulate trailing spaces
which were possibly trimmed earlier (e.g. in InnoDB CHAR compression).
This is important for NOPAD collations.
For example, with this input:
- str1= 'a ' (Latin letter a followed by one space)
- str2= 'a ' (Latin letter a followed by two spaces)
- nchars= 3
if the flag is given, strnncollsp_nchars() will virtually restore
one trailing space to str1 up to nchars (3) characters and compare two
strings as equal:
- str1= 'a ' (one extra trailing space emulated)
- str2= 'a ' (as is)
If the flag is not given, strnncollsp_nchars() does not add trailing
virtual spaces, so in case of a NOPAD collation, str1 will be compared
as less than str2 because it is shorter.
- Field_string::cmp_prefix() now passes the new flag.
Field_varstring::cmp_prefix() and Field_blob::cmp_prefix() do
not pass the new flag.
- The branch in cmp_whole_field() in storage/innobase/rem/rem0cmp.cc
(which handles the CHAR data type) now also passed the new flag.
- Fixing UCA collations to respect the new flag.
Other collations are possibly also affected, however
I had no success in making an SQL script demonstrating the problem.
Other collations will be extended to respect this flags in a separate
patch later.
- Changing the meaning of the last parameter of Field::cmp_prefix()
from "number of bytes" (internal length)
to "number of characters" (user visible length).
The code calling cmp_prefix() from handler.cc was wrong.
After this change, the call in handler.cc became correct.
The code calling cmp_prefix() from key_rec_cmp() in key.cc
was adjusted according to this change.
- Old strnncollsp_nchar() related tests in unittest/strings/strings-t.c
now pass the new flag.
A few new tests also were added, without the flag.
Also fixes:
MDEV-27768 MDEV-25440: Assertion `(cs->state & 0x20000) == 0' failed in my_strnncollsp_nchars_generic_8bit
The "strnncollsp_nchars" virtual function pointer for tis620_thai_nopad_ci
was incorrectly initialized to a generic function
my_strnncollsp_nchars_generic_8bit(), which crashed on assert.
Implementing a tis620 specific function version.
Summary of changes
- MD_CTX_SIZE is increased
- EVP_CIPHER_CTX_buf_noconst(ctx) does not work anymore, points
to nobody knows where. The assumption made previously was that
(since the function does not seem to be documented)
was that it points to the last partial source block.
Add own partial block buffer for NOPAD encryption instead
- SECLEVEL in CipherString in openssl.cnf
had been downgraded to 0, from 1, to make TLSv1.0 and TLSv1.1 possible
(according to https://github.com/openssl/openssl/blob/openssl-3.0.0/NEWS.md
even though the manual for SSL_CTX_get_security_level claims that it
should not be necessary)
- Workaround Ssl_cipher_list issue, it now returns TLSv1.3 ciphers,
in addition to what was set in --ssl-cipher
- ctx_buf buffer now must be aligned to 16 bytes with openssl(
previously with WolfSSL only), ot crashes will happen
- updated aes-t , to be better debuggable
using function, rather than a huge multiline macro
added test that does "nopad" encryption piece-wise, to test
replacement of EVP_CIPHER_CTX_buf_noconst
part of MDEV-29000
Summary of changes
- MD_CTX_SIZE is increased
- EVP_CIPHER_CTX_buf_noconst(ctx) does not work anymore, points
to nobody knows where. The assumption made previously was that
(since the function does not seem to be documented)
was that it points to the last partial source block.
Add own partial block buffer for NOPAD encryption instead
- SECLEVEL in CipherString in openssl.cnf
had been downgraded to 0, from 1, to make TLSv1.0 and TLSv1.1 possible
(according to https://github.com/openssl/openssl/blob/openssl-3.0.0/NEWS.md
even though the manual for SSL_CTX_get_security_level claims that it
should not be necessary)
- Workaround Ssl_cipher_list issue, it now returns TLSv1.3 ciphers,
in addition to what was set in --ssl-cipher
- ctx_buf buffer now must be aligned to 16 bytes with openssl(
previously with WolfSSL only), ot crashes will happen
- updated aes-t , to be better debuggable
using function, rather than a huge multiline macro
added test that does "nopad" encryption piece-wise, to test
replacement of EVP_CIPHER_CTX_buf_noconst
part of MDEV-28133
This fixed the MySQL bug# 20338 about misuse of double underscore
prefix __WIN__, which was old MySQL's idea of identifying Windows
Replace it by _WIN32 standard symbol for targeting Windows OS
(both 32 and 64 bit)
Not that connect storage engine is not fixed in this patch (must be
fixed in "upstream" branch)
This change removed 68 explict strlen() calls from the code.
The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name
Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible
Other things:
- There where compiler issues with ensuring that all character set names
points to the same string: gcc doesn't allow one to use integer constants
when defining global structures (constant char * pointers works fine).
To get around this, I declared defines for each character set name
length.
This patch adds support for right aligned strings and numbers.
Left alignment is left as an exercise for anyone needing it.
MDEV-25612 "Assertion `to <= end' failed in process_args" fixed.
(Was caused by the original version of this patch)
One should not change the program arguments!
This change also reduces warnings from the icc compiler.
Almost all changes are just syntax changes (adding const to
'get_one_option function' declarations).
Other changes:
- Added a few cast of 'argument' from 'const char*' to 'char *'. This
was mainly in calls to 'external' functions we don't have control of.
- Ensure that all reset of 'password command line argument' are similar.
(In almost all cases it was just adding a comment and a cast)
- In mysqlbinlog.cc and mysqld.cc there was a few cases that changed
the command line argument. These places where changed to instead allocate
the option in a MEM_ROOT to avoid changing the argument. Some of this
code was changed to ensure that different programs did parsing the
same way. Added a test case for the changes in mysqlbinlog.cc
- Changed a few variables that took their value from command line options
from 'char *' to 'const char *'.
This was because OpenBSD (and others) can be missing HAVE_BACKTRACE / HAVE_BACKTRACE_FD
which is the condition for my_safe_print_str to be defined.
Fixes:
/prj/tmp/work/cortexa57-poky-linux-musl/mariadb/10.5.8-r0/recipe-sysroot-native/usr/bin/aarch64-poky-linux-musl/../../libexec/aarch64-poky-linux-musl/gcc/aarch64-poky-linux-musl/10.2.0/ld.bfd: /usr/src/debug/mariadb/10.5.8-r0/mariadb-10.5.8/unittest/mysys/stacktrace-t.c:36: undefined reference to `my_safe_print_str'
Signed-off-by: Mingli Yu <mingli.yu@windriver.com>
