Description:
A deadlock occurred while truncate was executing;
When I execute truncate it locks the entire adaptive hash table.
When I find a block that has an adaptive hash.
I'm going to add an X lock to the adaptive hash table,Then a deadlock occurs.
The following code.
fil_reinit_space_header_for_table
btr_search_s_lock_all();
DEBUG_SYNC_C("simulate_buffer_pool_scan");
buf_LRU_flush_or_remove_pages(id, BUF_REMOVE_ALL_NO_WRITE, 0);
btr_search_s_unlock_all();
buf_LRU_drop_page_hash_for_tablespace
buf_LRU_drop_page_hash_batch
btr_search_drop_page_hash_when_freed
btr_search_drop_page_hash_index
btr_search_drop_page_hash_index
rw_lock_x_lock(latch);
How to repeat:
1:Comment out the following code
if (ahi) {
//btr_search_drop_page_hash_when_freed(page_id, page_size);
}
if (ahi) {
for (i = 0; i < FSP_EXTENT_SIZE; i++) {
if (!xdes_mtr_get_bit(descr, XDES_FREE_BIT, i, mtr)) {
/* Drop search system page hash index
if the page is found in the pool and
is hashed */
//btr_search_drop_page_hash_when_freed(
// page_id_t(space,
// first_page_in_extent + i),
// page_size);
}
}
}
2:Frequent access to table T1 causes table T1 to generate adaptive hash data
3:truncate T1;
Suggested fix:
When we execute the function:fil_reinit_space_header_for_table,We don't have to clean up adaptive hashes.
If we clean up adaptive hashes, a deadlock will occur.
Description: A deadlock occurred while truncate was executing; When I execute truncate it locks the entire adaptive hash table. When I find a block that has an adaptive hash. I'm going to add an X lock to the adaptive hash table,Then a deadlock occurs. The following code. fil_reinit_space_header_for_table btr_search_s_lock_all(); DEBUG_SYNC_C("simulate_buffer_pool_scan"); buf_LRU_flush_or_remove_pages(id, BUF_REMOVE_ALL_NO_WRITE, 0); btr_search_s_unlock_all(); buf_LRU_drop_page_hash_for_tablespace buf_LRU_drop_page_hash_batch btr_search_drop_page_hash_when_freed btr_search_drop_page_hash_index btr_search_drop_page_hash_index rw_lock_x_lock(latch); How to repeat: 1:Comment out the following code if (ahi) { //btr_search_drop_page_hash_when_freed(page_id, page_size); } if (ahi) { for (i = 0; i < FSP_EXTENT_SIZE; i++) { if (!xdes_mtr_get_bit(descr, XDES_FREE_BIT, i, mtr)) { /* Drop search system page hash index if the page is found in the pool and is hashed */ //btr_search_drop_page_hash_when_freed( // page_id_t(space, // first_page_in_extent + i), // page_size); } } } 2:Frequent access to table T1 causes table T1 to generate adaptive hash data 3:truncate T1; Suggested fix: When we execute the function:fil_reinit_space_header_for_table,We don't have to clean up adaptive hashes. If we clean up adaptive hashes, a deadlock will occur.