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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. |
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embedded | ||
examples | ||
json_lib | ||
my_decimal | ||
mysys | ||
mytap | ||
sql | ||
strings | ||
README.txt | ||
unit.pl |
Unit tests directory structure ------------------------------ This is the current structure of the unit tests. More directories will be added over time. mytap Source for the MyTAP library mysys Tests for mysys components bitmap-t.c Unit test for MY_BITMAP base64-t.c Unit test for base64 encoding functions examples Example unit tests. core-t.c Example of raising a signal in the middle of the test THIS TEST WILL STOP ALL FURTHER TESTING! simple-t.c Example of a standard TAP unit test skip-t.c Example where some test points are skipped skip_all-t.c Example of a test where the entire test is skipped todo-t.c Example where test contain test points that are TODO no_plan-t.c Example of a test with no plan (avoid this) Executing unit tests -------------------- To make and execute all unit tests in the directory: make test Observe that the tests in the examples/ directory are just various examples of tests and are not expected to pass. Adding unit tests ----------------- Add a file with a name of the format "foo-t.c" to the appropriate directory and add the following to the Makefile.am in that directory (where ... denotes stuff already there): noinst_PROGRAMS = ... foo-t Note, it's important to have "-t" at the end of the filename, otherwise the test won't be executed by 'make test' ! Documentation ------------- The generated documentation is temporarily placed at: http://www.kindahl.net/mytap/doc/ I will move it to a better place once I figure out where and how.