我们在 PR 和 DR 上有两个 mariadb 服务器 Master 和 Slave，我们观察到高磁盘 io 超过 90% 并且 iowait 一段时间超过 20，当 mariadb 备份在晚上开始时 iowait 超过 30 并且系统变得无响应导致看门狗进程超时和重启mariadb。当运行 dd 命令 sudo dd if=/dev/zero of=/data/test2.img bs=512 count=1000 oflag=dsync 它写入数据在 300 到 500 Kb/s 之间，我们也检查了存储级别，但没有问题在存储级别发现相同的存储已用于其他数据库（Oracle），并且没有此类 IO 问题。我需要帮助来确定这个问题。以下是mariadb的server.cnf
[mysqld]
symbolic_links = 0
local_infile = 0
basedir = /usr
datadir = /data/mdb_data
pid_file = /var/lib/mysql/mysqld.pid
log_error = /var/log/mariadb/mysqld.log
bind-address = ::
port = 3306
userstat = 1
plugin-load-add = server_audit=server_audit.so
server_audit = FORCE_PLUS_PERMANENT
server_audit_logging = on
server_audit_events = CONNECT,QUERY_DCL,QUERY_DDL
server_audit_output_type = syslog
cracklib_password_check = off
log_bin_trust_function_creators = 1
lower_case_table_names = 1
character-set-server = utf8
init_connect = SET NAMES utf8
innodb_file_per_table = 1
innodb_flush_log_at_trx_commit = 1
skip-name-resolve
innodb_autoinc_lock_mode = 2
max_connections = 3000
innodb_buffer_pool_size = 58G
innodb_buffer_pool_instances = 8
innodb_log_file_size = 1024m
key_buffer_size = 16M
log-error = /var/log/mariadb/mysqld.log
skip-external-locking
slow_query_log = on
long_query_time = 1
slow_query_log_file = /var/log/mariadb/slowSQLs.log
performance_schema = on
innodb_flush_method = O_DIRECT
sync_binlog = 1
max_allowed_packet = 512m
slave_max_allowed_packet = 200m
innodb_read_io_threads = 32
innodb_write_io_threads = 32
innodb_io_capacity = 600
slave_parallel_threads = 50
slave_parallel_max_queued = 2097152
slave_parallel_mode = optimistic
rpl_semi_sync_master_enabled = 0
rpl_semi_sync_slave_enabled = 1
rpl_semi_sync_master_wait_point = AFTER_SYNC
binlog_commit_wait_usec = 10000
binlog_commit_wait_count = 1
server_audit_excl_users = repl@b.c,maxscale
slave-skip-errors = 1062,1032
[mysqld_safe]
syslog
[mariadb]
server_id = 228575792
log_slave_updates = on
log-bin
log-basename = db2
report_host = db2
从顶部
KiB Mem : 74046272 total, 32528492 free, 26723664 used, 14794120 buff/cache
KiB Swap: 33554428 total, 31482364 free, 2072064 used. 33507036 avail Mem