-Mariadb 10.5.13带有Galera群集：偶尔信号11在高交易负载期间使用get_lock/Release_lost撞击 环境： 我正在使用Galera群集设置的Mariadb 10.5.13。 InnoDB存储引擎。 实例类型：AWS T3.Medium。 内存使用详细信息： 。 my.cnf配置： ＃ ＃这些组由

Question

记忆用法详细信息：

。

My.cnf配置：

#
# These groups are read by MariaDB server.
# Use it for options that only the server (but not clients) should see
#
# See the examples of server my.cnf files in /usr/share/mysql/
#

# this is read by the standalone daemon and embedded servers
[server]
basedir=/home/admin/service/mariadb
aria_log_dir_path=/home/admin/service/mariadb/data/
character_sets_dir=/home/admin/service/mariadb/share/charsets/
datadir=/home/admin/service/mariadb/data/
pid_file=/home/admin/service/mariadb/data/mariadb.pid
plugin_dir=/home/admin/service/mariadb/lib/plugin/
flashback=On
innodb_flush_method=O_DIRECT
innodb_lock_schedule_algorithm=VATS
# deprecated 10.5
#innodb_scrub_log=FALSE
default_storage_engine=InnoDB
default_time_zone='+0:00'
binlog_checksum = CRC32
## not used character_set_client = utf8mb4
## not used character_set_connection = utf8mb4
## not used character_set_database   = utf8mb4
## not used character_set_results    = utf8mb4
## not used collation_connection     = utf8mb4_unicode_ci
character_set_filesystem = binary
character_set_server     = utf8mb4
collation_server         = utf8mb4_unicode_ci
character_set_client_handshake=FALSE
ft_max_word_len=84
ft_min_word_len=1
innodb_adaptive_flushing=1
innodb_adaptive_hash_index=1
innodb_default_row_format=DYNAMIC
innodb_file_per_table=1
innodb_ft_max_token_size=252
innodb_ft_min_token_size=1
#innodb_large_prefix=1
# deprecated 10.5
#innodb_log_checksums=1
innodb_log_compressed_pages=1
#on 4gb
innodb_log_file_size=192M
innodb_strict_mode=1
innodb_autoinc_lock_mode=2
innodb_random_read_ahead=1
innodb_use_native_aio=1
sync_binlog=1
innodb_flush_log_at_trx_commit=1
log_bin_trust_function_creators=1
thread_handling=pool-of-threads
event_scheduler=ON
innodb_buffer_pool_dump_at_shutdown=1
innodb_buffer_pool_load_at_startup=1
innodb_defragment=1
default_storage_engine=InnoDB
binlog_format=ROW
innodb_strict_mode=1
log_basename=mariadb
log_bin
log-error
log_bin_compress=ON
master_verify_checksum=ON
memlock=ON
myisam_use_mmap=ON
query_cache_type=ON
query-cache-wlock-invalidate=ON
query_cache_size=1048576
slow_query_log=ON
#ssl                                                        FALSE

# deprecated 10.5
#innodb_buffer_pool_instances=2
slave_parallel_mode=optimistic
innodb_buffer_pool_size=700M
key_buffer_size=20M
#(4*1024*1024*1024-(437*1024*1024)-300*1024*1024)/(19*1024*1024)
#(total mem - (437mb, global) - (300mb, os) ) / (19mb, thread per conn)
#on 4gb
max_connections=128
performance_schema = ON
gtid_strict_mode=1
slave_compressed_protocol=1
wait_timeout=150
table_definition_cache=512
skip-name-resolve=1

# this is only for embedded server
[embedded]

# this is only for the mysqld standalone daemon
[mysqld]

#
# * Galera-related settings
#
[galera]
#VATS should not be used with Galera
innodb_lock_schedule_algorithm=FCFS
# Query cache cannot be used in a Galera context..
query_cache_type = 0
query_cache_size = 0
memlock=OFF
# Mandatory settings
wsrep_on=ON
wsrep_auto_increment_control=ON
wsrep_provider=/home/admin/service/mariadb/lib/libgalera_smm.so
wsrep_cluster_address='gcomm://private dns~~,~~ , ~~’
## gcs.fc_limit= wsrep_slave_threads * 5
wsrep_provider_options='gcache.size=512M;gcache.recover=yes;pc.recovery=yes;gcs.fc_limit=20;gcs.fc_factor = 0.8;gcs.fc_master_slave=yes'
wsrep_cluster_name=main_db_cluster
#
# Allow server to accept connections on all interfaces.
#
bind-address=0.0.0.0
#
# Optional setting
wsrep_slave_threads=4
#IST or SST will recover from loss
innodb_flush_log_at_trx_commit=0
innodb_doublewrite=1
wsrep_auto_increment_control=1
wsrep_gtid_mode=ON
wsrep_sst_auth=admin
wsrep_sst_method=mariabackup
# first use
#wsrep_sst_method=rsync
log-slave-updates=ON

sissue： 数据库有时会以信号11错误崩溃。 （我知道Galera群集不支持Get_lock和Release_lock，但是在我意识到此限制之前，该代码是编写的。）

问题： 我知道GALERA群集不支持Get_lock和Release_lock，但是这些查询是否可能导致内存问题导致崩溃？查询通常运行良好，但是每隔几个月，数据库就会崩溃。我不确定问题是与查询本身有关还是与内存过载有关。

问题场景： 方案1：

---

00:08和00:09之间，大约1000个数据库交易发生在一分钟之内。每个交易都使用get_lock和Release_lock获取锁并修改特定行。

数据库收到信号11错误。

---

25分钟后，数据库崩溃了信号6错误。

2. 
   Scenario2：
3. 00:08和00:09之间，大约1000个数据库交易发生在一分钟之内。每个交易都使用get_lock和Release_lock获取锁并修改特定行。
   数据库遇到了一个segfault，收到了信号11错误并崩溃了。 。 .

日志显示Release_lock与有问题的查询有关。

请让我知道查询是否有更具体的问题，还是我实例上的内存限制是否可能导致这些崩溃。

1. 我将向您展示查询的一部分。敏感信息已被缩写，但是总体流量和查询是相同的。

This process involves retrieving stores and calculating the order amount for the day in a loop.  
The schema is structured in a typical manner, consisting of company(store), bucket, bucket_item, product and tx(company transaction).

[1] Retrieve the companies.
[2] Loop through the companies.
[3] Begin a transaction.
[4] Retrieve the company bucket (locking read).
[5] Create an internal transaction.
[6] Retrieve the products in the bucket (locking read).
[7] Update the total price of the bucket.
[8] Create a user lock.
[9] Register the store ledger(tx).
[10] Release the user lock.
[11] Link the order to the ledger(tx).
[12] The transactions are then sequentially closed.


-----
[1]
Select company 
Result : 1000

[2]
loop {

[3]
<root transcation start>

[4]
SELECT
    b.id                    AS id
FROM bucket AS b
WHERE
b.id IN (#{bucketSeq})
FOR UPDATE

[5]
<nested transaction start>

[6]
WITH product_mapping AS (
    SELECT
        p.id                     AS product_seq
    FROM product p
)
SELECT
    bi.id                            AS id,
    bi.product_seq                   AS product_seq
FROM bucket_item AS bi
         LEFT JOIN product_mapping pm ON pm.product_seq = bi.product_seq
WHERE bi.bucket_seq = #{bucketSeq}
    AND bi.type=#{bucketItemType}
GROUP BY bi.id
FOR UPDATE

[7]
UPDATE bucket AS b
SET b.total_price=#{totalPrice},
    b.total_cost=#{totalCost},
    b.priced_at=#{pricedAt},
    b.total_price_tax_free=
        (SELECT IFNULL(SUM(bi.unit_price * bi.amount), 0)
         FROM bucket_item AS bi
         JOIN product AS p ON p.id = bi.product_seq
         WHERE bi.bucket_seq = b.id)
WHERE b.id=#{bucketSeq}

[8]
<get Lock>
SELECT GET_LOCK(CONCAT("AA_", #{key}), #{timeoutSeconds})
</get lock>

[9]
INSERT INTO tx (
    happened_at,
    balance
)
    (
        SELECT
            #{happenedAt} AS happened_at,
            IFNULL(lbb.balance,0)+(#{amount}) AS balance
        FROM company AS c
             LEFT JOIN (SELECT
                            t.company_seq AS company_seq,
                            t.balance AS balance
                        FROM tx AS t
                        WHERE t.company_seq = #{companySeq}
                        ORDER BY t.happened_at DESC
                        LIMIT 1
        ) AS lbb ON c.id=lbb.company_seq
        WHERE c.id=#{companySeq}
        LIMIT 1
    )

[10]
< release lock>
SELECT RELEASE_LOCK(CONCAT("AA_", #{key}))
</release lock>

[11]
INSERT INTO bucket_tx (
    happened_at,
    bucket_seq,
    tx_seq
)
    (
        SELECT
            t.happened_at AS happened_at,
            b.id AS bucket_seq,
            t.id AS tx_seq
        FROM
            seq_1_to_1
                JOIN bucket AS b ON b.id = #{bucketSeq}
                JOIN tx AS t ON t.id = #{txSeq}
        WHERE
            NOT EXISTS (
                    SELECT
                        1
                    FROM
                        bucket_tx AS bt
                    WHERE
                        bt.tx_seq = #{txSeq}
                      AND bt.bucket_seq = #{bucketSeq}
                )
        LIMIT 1
    )

[12]
<close nested transaction>
<close root transaction>
}

2. 
   它是一个有问题的数据库版本。 我们需要继续进行版本更新。 Reference：Https：//jira.mariadb.org/browse/mdev-24143