mariadb/extra/mariabackup
Marko Mäkelä 9c8bdc6c15 MDEV-35049: btr_search_check_free_space_in_heap() is a bottleneck
Let us use implement a simple fixed-size allocator for the adaptive hash
index, insted of complicating mem_heap_t or mem_block_info_t.

MEM_HEAP_BTR_SEARCH: Remove.

mem_block_info_t::free_block(), mem_heap_free_block_free(): Remove.

mem_heap_free_top(), mem_heap_get_top(): Remove.

btr_sea::partition::spare: Replaces mem_block_info_t::free_block.
This keeps one spare block per adaptive hash index partition, to
process an insert.

We must not wait for buf_pool.mutex while holding
any btr_sea::partition::latch. That is why we cache one block for
future allocations. This is protected by a new
btr_sea::partition::blocks_mutex in order to relieve pressure on
btr_sea::partition::latch.

btr_sea::partition::prepare_insert(): Replaces
btr_search_check_free_space_in_heap().

btr_sea::partition::erase(): Replaces ha_search_and_delete_if_found().

btr_sea::partition::cleanup_after_erase(): Replaces the most part of
ha_delete_hash_node(). Unlike the previous implementation, we will
retain a spare block for prepare_insert().
This should reduce some contention on buf_pool.mutex.

btr_search.n_parts: Replaces btr_ahi_parts.

btr_search.enabled: Replaces btr_search_enabled. This must hold
whenever buf_block_t::index is set while a thread is holding a
btr_sea::partition::latch.

dict_index_t::search_info: Remove pointer indirection, and use
Atomic_relaxed or Atomic_counter for most fields.

btr_search_guess_on_hash(): Let the caller ensure that latch_mode is
BTR_MODIFY_LEAF or BTR_SEARCH_LEAF. Release btr_sea::partition::latch
before buffer-fixing the block. The page latch that we already acquired
is preventing buffer pool eviction. We must validate both
block->index and block->page.state while holding part.latch
in order to avoid race conditions with buffer page relocation
or buf_pool_t::resize().

btr_search_check_guess(): Remove the constant parameter
can_only_compare_to_cursor_rec=false.

ahi_node: Replaces ha_node_t.

This has been tested by running the regression test suite
with the adaptive hash index enabled:
./mtr --mysqld=--loose-innodb-adaptive-hash-index=ON

Reviewed by: Vladislav Lesin
2025-01-10 16:30:42 +02:00
..
quicklz
aria_backup_client.cc
aria_backup_client.h
backup_copy.cc
backup_copy.h
backup_debug.h
backup_mysql.cc
backup_mysql.h
backup_wsrep.h
CMakeLists.txt
common.h
common_engine.cc
common_engine.h
datasink.cc
datasink.h
ddl_log.cc
ddl_log.h
ds_buffer.cc
ds_buffer.h
ds_compress.cc
ds_compress.h
ds_local.cc
ds_local.h
ds_stdout.cc
ds_stdout.h
ds_tmpfile.cc
ds_tmpfile.h
ds_xbstream.cc
ds_xbstream.h
encryption_plugin.cc
encryption_plugin.h
fil_cur.cc
fil_cur.h
innobackupex.cc
innobackupex.h
read_filt.cc
read_filt.h Cleanup: Remove changed_pages_bitmap 2024-02-12 17:01:35 +02:00
thread_pool.cc
thread_pool.h
write_filt.cc
write_filt.h
wsrep.cc
xb_regex.h
xbcloud.cc
xbstream.cc Merge 10.11 into 11.4 2024-12-02 11:35:34 +02:00
xbstream.h
xbstream_read.cc
xbstream_write.cc
xtrabackup.cc
xtrabackup.h