Monty e600f9aebb MDEV-35750 Change MEM_ROOT allocation sizes to reduse calls to malloc() and avoid memory fragmentation ... This commit updates default memory allocations size used with MEM_ROOT objects to minimize the number of calls to malloc(). Changes: - Updated MEM_ROOT block sizes in sql_const.h - Updated MALLOC_OVERHEAD to also take into account the extra memory allocated by my_malloc() - Updated init_alloc_root() to only take MALLOC_OVERHEAD into account as buffer size, not MALLOC_OVERHEAD + sizeof(USED_MEM). - Reset mem_root->first_block_usage if and only if first block was used. - Increase MEM_ROOT buffers sized used by my_load_defaults, plugin_init, Create_tmp_table, allocate_table_share, TABLE and TABLE_SHARE. This decreases number of malloc calls during queries. - Use a small buffer for THD->main_mem_root in THD::THD. This avoids multiple malloc() call for new connections. I tried the above changes on a complex select query with 12 tables. The following shows the number of extra allocations that where used to increase the size of the MEM_ROOT buffers. Original code: - Connection to MariaDB: 9 allocations - First query run: 146 allocations - Second query run: 24 allocations Max memory allocated for thd when using with heap table: 61,262,408 Max memory allocated for thd when using Aria tmp table: 419,464 After changes: Connection to MariaDB: 0 allocations - First run: 25 allocations - Second run: 7 allocations Max memory allocated for thd when using with heap table: 61,347,424 Max memory allocated for thd when using Aria table: 529,168 The new code uses slightly more memory, but avoids memory fragmentation and is slightly faster thanks to much fewer calls to malloc(). Reviewed-by: Sergei Golubchik <serg@mariadb.org>		2025-01-05 16:40:11 +02:00
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crc32
array.c
base64.c
ChangeLog
charset-def.c
charset.c
CMakeLists.txt
crc32ieee.cc
errors.c
file_logger.c
get_password.c
guess_malloc_library.c
hash.c
lf_alloc-pin.c
lf_dynarray.c
lf_hash.cc
list.c
ma_dyncol.c
mf_arr_appstr.c
mf_cache.c
mf_dirname.c
mf_fn_ext.c
mf_format.c
mf_getdate.c
mf_iocache.c
mf_iocache2.c
mf_keycache.c
mf_keycaches.c
mf_loadpath.c
mf_pack.c
mf_path.c
mf_qsort.c
mf_qsort2.c
mf_radix.c
mf_same.c
mf_sort.c
mf_soundex.c
mf_tempdir.c
mf_tempfile.c
mf_unixpath.c
mf_wcomp.c
mulalloc.c
my_access.c
my_addr_resolve.c
my_alarm.c
my_alloc.c
my_atomic_writes.c
my_basename.c
my_bit.c
my_bitmap.c
my_chmod.c
my_chsize.c
my_compare.c
my_compress.c
my_conio.c
my_copy.c
my_cpu.c
my_create.c
my_default.c
my_delete.c
my_div.c
my_dlerror.c
my_error.c
my_file.c
my_fopen.c
my_fstream.c
my_getexe.c
my_gethwaddr.c
my_getncpus.c
my_getopt.c
my_getpagesize.c
my_getsystime.c
my_getwd.c
my_init.c
my_largepage.c
my_lib.c
my_libwrap.c
my_likely.c
my_lock.c
my_lockmem.c
my_malloc.c
my_memmem.c
my_mess.c
my_minidump.cc
my_mkdir.c
my_mmap.c
my_new.cc
my_once.c
my_open.c
my_port.c
my_pread.c
my_pthread.c
my_quick.c
my_rdtsc.c
my_read.c
my_redel.c
my_rename.c
my_rnd.c
my_safehash.c
my_safehash.h
my_seek.c
my_setuser.c
my_sleep.c
my_stack.c
my_static.c
my_static.h
my_symlink.c
my_symlink2.c
my_sync.c
my_thr_init.c
my_uuid.c
my_win_popen.cc
my_wincond.c
my_winerr.c
my_winfile.c
my_winthread.c
my_wintoken.c
my_write.c
mysys_priv.h
psi_noop.c
ptr_cmp.c
queues.c
safemalloc.c
stacktrace.c
string.c
test_charset.c
test_dir.c
test_thr_mutex.c
test_xml.c
testhash.c
thr_alarm.c
thr_lock.c
thr_mutex.c
thr_rwlock.c
thr_timer.c
tree.c
typelib.c
waiting_threads.c
wqueue.c