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I'm running into issues after upgrading from mysql 5.5 to mysql ver 14.14 distrib 5.7.16 on CentOS Linux release 7.2.1511 (Core)

mysql systemd: Stopping user-0.slice.
mysql kernel: mysqld invoked oom-killer: gfp_mask=0x280da, order=0, oom_score_adj=0
mysql kernel: mysqld cpuset=/ mems_allowed=0
mysql kernel: CPU: 0 PID: 30238 Comm: mysqld Not tainted 3.10.0-327.36.3.el7.x86_64 #1
mysql kernel: Hardware name: Xen HVM domU, BIOS 4.2.amazon 11/11/2016 

dmesg

[461124.941170] Out of memory: Kill process 30048 (mysqld) score 980 or sacrifice child
[461124.946789] Killed process 30048 (mysqld) total-vm:31170916kB, anon-rss:30313888kB, file-rss:0kB

Server: r3.xlarge 4 vCPU and 30.5GB Memory

swap is not enabled.

max_allowed_packet: 1073741824

Should I need to change innodb_log_file_size = 1000M to 25% of innodb_buffer_pool_size=12G ?

Any help would be much appreciated!

/etc/my.cnf

[mysql.server]
service-startup-timeout = -1

[client]
port=3306

[mysql]
default-character-set=utf8

[mysqld]
relay-log=/mnt/data/mysql/mysqld-relay-bin
innodb_flush_method = O_DIRECT
tmpdir=/mnt/data/tmp
binlog-format=row
port = 3306
max_allowed_packet = 1G
socket = /var/lib/mysql/mysql.sock
user = mysql
lower_case_table_names = 1
log_bin_trust_function_creators = 1
slave-net-timeout = 60
log-bin = mysql-bin
expire_logs_days=21
server-id = 162
datadir=/mnt/data/mysql
character-set-server = utf8
default-storage-engine = INNODB
sql-mode = "STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
max_connections=4000
query_cache_size=0
query_cache_limit=0
query_cache_type=0
table_open_cache = 1520
log-error = /var/log/mysqld.log
tmp_table_size = 1G
max_heap_table_size = 1G
thread_cache_size = 120
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 40M
innodb_buffer_pool_size=12G
innodb_log_file_size = 1000M
innodb_thread_concurrency = 8
log-queries-not-using-indexes
long_query_time=1
wait_timeout=43200
interactive_timeout=43200
innodb_lock_wait_timeout = 120
group_concat_max_len = 1M
innodb-file-per-table = 1
innodb-flush-method = O_DIRECT
innodb-thread-concurrency = 0
sync_binlog = 1
slow-query-log = 1
slow-query-log-file = /mnt/data/mysql/mysql_slow_queries.log
skip_ssl
skip_name_resolve
explicit_defaults_for_timestamp = 0
innodb_buffer_pool_instances = 1
innodb_page_cleaners = 1
event_scheduler = ON

[mysqld_safe]
timezone = UTC

mysqld.service:

[Unit]
Description=MySQL Server
After=network.target
After=syslog.target

[Install]
WantedBy=multi-user.target

[Service]
User=mysql
Group=mysql
Type=forking
PIDFile=/var/run/mysqld/mysqld.pid
TimeoutSec=300
PermissionsStartOnly=true
ExecStartPre=/bin/mkdir -p /var/run/mysqld
ExecStartPre=/bin/chown -R mysql:mysql /mnt/data/
ExecStartPre=/bin/chown -R mysql:mysql /var/lib/mysql/
ExecStartPre=/bin/chown -R mysql:mysql /var/run/mysqld/
ExecStartPre=/usr/bin/mysqld_pre_systemd
ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS
EnvironmentFile=-/etc/sysconfig/mysql
LimitNOFILE=40000
LimitMEMLOCK=infinity
Restart=on-failure
RestartPreventExitStatus=1
PrivateTmp=false

ulimit -a

core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 121914
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 65535
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 65535
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

mysqltuner

[OK] Operating on 64-bit architecture
Log file Recommendations

[--] Log file: /var/log/mysqld.log(1M)
[OK] Log file /var/log/mysqld.log exists
[OK] Log file /var/log/mysqld.log is readable.
[OK] Log file /var/log/mysqld.log is not empty
[OK] Log file /var/log/mysqld.log is smaller than 32 Mb
[!!] /var/log/mysqld.log contains 1592 warning(s).
[!!] /var/log/mysqld.log contains 6323 error(s).
[--] 10 start(s) detected in /var/log/mysqld.log
12 shutdown(s) detected in /var/log/mysqld.log

Storage Engine Statistics
[--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MEMORY +MRG_MYISAM +MyISAM +PERFORMANCE_SCHEMA
[--] Data in MyISAM tables: 12K (Tables: 9)
[--] Data in InnoDB tables: 7638G (Tables: 3497)
[!!] Total fragmented tables: 2

-------- Performance Metrics
[--] Up for: 10h 17m 16s (31M q [838.327 qps], 20K conn, TX: 123G, RX: 24G)
[--] Reads / Writes: 68% / 32%
[--] Binary logging is enabled (GTID MODE: OFF)
[--] Physical Memory     : 29.6G
[--] Max MySQL memory    : 17.4G
[--] Other process memory: 149.8M
[--] Total buffers: 13.0G global + 1.1M per thread (4000 max threads)
[--] P_S Max memory usage: 72B
[--] Galera GCache Max memory usage: 0B
[OK] Maximum reached memory usage: 13.5G (45.72% of installed RAM)
[OK] Maximum possible memory usage: 17.4G (59.02% of installed RAM)
[OK] Overall possible memory usage with other process is compatible with memory available
[OK] Slow queries: 1% (379K/31M)
[OK] Highest usage of available connections: 10% (423/4000)
[OK] Aborted connections: 0.02%  (5/20354)
[OK] Query cache is disabled by default due to mutex contention on multiprocessor machines.
[!!] Sorts requiring temporary tables: 12% (65K temp sorts / 514K sorts)
[!!] Joins performed without indexes: 60429
[OK] Temporary tables created on disk: 12% (121K on disk / 972K total)
[OK] Thread cache hit rate: 97% (487 created / 20K connections)
[!!] Table cache hit rate: 0% (1K open / 975K opened)
[OK] Open file limit used: 0% (78/40K)
[OK] Table locks acquired immediately: 100% (31K immediate / 31K locks)
[OK] Binlog cache memory access: 99.35% (705658 Memory / 710308 Total)

-------- Performance schema ------------------------------------------------------------------------
[--] Performance schema is enabled.
[--] Memory used by P_S: 72B
[--] Sys schema is installed.

-------- ThreadPool Metrics ------------------------------------------------------------------------
[--] ThreadPool stat is disabled.

-------- MyISAM Metrics ----------------------------------------------------------------------------
[!!] Key buffer used: 18.3% (1M used / 8M cache)
[OK] Key buffer size / total MyISAM indexes: 8.0M/81.0K
[OK] Read Key buffer hit rate: 99.7% (68K cached / 194 reads)
[!!] Write Key buffer hit rate: 0.0% (32 cached / 32 writes)

-------- InnoDB Metrics ----------------------------------------------------------------------------
[--] InnoDB is enabled.
[--] InnoDB Thread Concurrency: 0
[OK] InnoDB File per table is activated
[!!] InnoDB buffer pool / data size: 12.0G/7638.7G
[!!] Ratio InnoDB log file size / InnoDB Buffer pool size (16.2760416666667 %): 1000.0M * 2/12.0G should be equal 25%
[!!] InnoDB buffer pool instances: 1
[--] Number of InnoDB Buffer Pool Chunk : 96 for 1 Buffer Pool Instance(s)
[OK] Innodb_buffer_pool_size aligned with Innodb_buffer_pool_chunk_size & Innodb_buffer_pool_instances
[OK] InnoDB Read buffer efficiency: 99.99% (20560413998 hits/ 20562576302 total)
[OK] InnoDB Write log efficiency: 96.90% (23550427 hits/ 24303035 total)
[OK] InnoDB log waits: 0.00% (0 waits / 752608 writes)

-------- AriaDB Metrics ----------------------------------------------------------------------------
[--] AriaDB is disabled.

-------- TokuDB Metrics ----------------------------------------------------------------------------
[--] TokuDB is disabled.

-------- XtraDB Metrics ----------------------------------------------------------------------------
[--] XtraDB is disabled.

-------- RocksDB Metrics ---------------------------------------------------------------------------
[--] RocksDB is disabled.

-------- Spider Metrics ----------------------------------------------------------------------------
[--] Spider is disabled.

-------- Connect Metrics ---------------------------------------------------------------------------
[--] Connect is disabled.

-------- Galera Metrics ----------------------------------------------------------------------------
[--] Galera is disabled.

-------- Replication Metrics -----------------------------------------------------------------------
[--] Galera Synchronous replication: NO
[--] No replication slave(s) for this server.
[--] This is a standalone server.

-------- Recommendations ---------------------------------------------------------------------------
General recommendations:
    Control warning line(s) into /var/log/mysqld.log file
    Control error line(s) into /var/log/mysqld.log file
    Run OPTIMIZE TABLE to defragment tables for better performance
      OPTIMIZE TABLE prod.qc_connector_log; -- can free 1479 MB
      OPTIMIZE TABLE prod.transport_object; -- can free 1038 MB
    Total freed space after theses OPTIMIZE TABLE : 2517 Mb
    Set up a Secure Password for user@host ( SET PASSWORD FOR 'user'@'SpecificDNSorIp' = PASSWORD('secure_password'); )
    Restrict Host for user@% to user@SpecificDNSorIp
    MySQL started within last 24 hours - recommendations may be inaccurate
    Adjust your join queries to always utilize indexes
    Increase table_open_cache gradually to avoid file descriptor limits
    Read this before increasing table_open_cache over 64: http://bit.ly/1mi7c4C
    Beware that open_files_limit (40000) variable
    should be greater than table_open_cache (1520)
Variables to adjust:
    sort_buffer_size (> 256K)
    read_rnd_buffer_size (> 256K)
    join_buffer_size (> 256.0K, or always use indexes with joins)
    table_open_cache (> 1520)
    innodb_buffer_pool_size (>= 7638G) if possible.
    innodb_log_file_size should be equals to 1/4 of buffer pool size (=3G) if possible.
    innodb_buffer_pool_instances(=12)

There is IOWAIT, AFAIK this is not the reason of the crashes.

Crashed around 02:00 (zabbix screenshot attached)

SHOW VARIABLES;

auto_increment_increment    1
auto_increment_offset   1
autocommit  ON
automatic_sp_privileges ON
avoid_temporal_upgrade  OFF
back_log    850
basedir /usr/
big_tables  OFF
bind_address    *
binlog_cache_size   32768
binlog_checksum CRC32
binlog_direct_non_transactional_updates OFF
binlog_error_action ABORT_SERVER
binlog_format   ROW
binlog_group_commit_sync_delay  0
binlog_group_commit_sync_no_delay_count 0
binlog_gtid_simple_recovery ON
binlog_max_flush_queue_time 0
binlog_order_commits    ON
binlog_row_image    FULL
binlog_rows_query_log_events    OFF
binlog_stmt_cache_size  32768
block_encryption_mode   aes-128-ecb
bulk_insert_buffer_size 8388608
character_set_client    utf8
character_set_connection    utf8
character_set_database  utf8
character_set_filesystem    binary
character_set_results   utf8
character_set_server    utf8
character_set_system    utf8
character_sets_dir  /usr/share/mysql/charsets/
check_proxy_users   OFF
collation_connection    utf8_general_ci
collation_database  utf8_general_ci
collation_server    utf8_general_ci
completion_type NO_CHAIN
concurrent_insert   AUTO
connect_timeout 10
core_file   OFF
datadir /mnt/data/mysql/
date_format %Y-%m-%d
datetime_format %Y-%m-%d %H:%i:%s
default_authentication_plugin   mysql_native_password
default_password_lifetime   0
default_storage_engine  InnoDB
default_tmp_storage_engine  InnoDB
default_week_format 0
delay_key_write ON
delayed_insert_limit    100
delayed_insert_timeout  300
delayed_queue_size  1000
disabled_storage_engines     
disconnect_on_expired_password  ON
div_precision_increment 4
end_markers_in_json OFF
enforce_gtid_consistency    OFF
eq_range_index_dive_limit   200
error_count 0
event_scheduler ON
expire_logs_days    21
explicit_defaults_for_timestamp OFF
external_user    
flush   OFF
flush_time  0
foreign_key_checks  ON
ft_boolean_syntax   + -><()~*:""&|
ft_max_word_len 84
ft_min_word_len 4
ft_query_expansion_limit    20
ft_stopword_file    (built-in)
general_log OFF
general_log_file    /mnt/data/mysql/mysql.log
group_concat_max_len    1048576
gtid_executed_compression_period    1000
gtid_mode   OFF
gtid_next   AUTOMATIC
gtid_owned   
gtid_purged  
have_compress   YES
have_crypt  YES
have_dynamic_loading    YES
have_geometry   YES
have_openssl    DISABLED
have_profiling  YES
have_query_cache    YES
have_rtree_keys YES
have_ssl    DISABLED
have_statement_timeout  YES
have_symlink    YES
host_cache_size 803
hostname    mysql
identity    0
ignore_builtin_innodb   OFF
ignore_db_dirs   
init_connect     
init_file    
init_slave   
innodb_adaptive_flushing    ON
innodb_adaptive_flushing_lwm    10
innodb_adaptive_hash_index  ON
innodb_adaptive_hash_index_parts    8
innodb_adaptive_max_sleep_delay 150000
innodb_api_bk_commit_interval   5
innodb_api_disable_rowlock  OFF
innodb_api_enable_binlog    OFF
innodb_api_enable_mdl   OFF
innodb_api_trx_level    0
innodb_autoextend_increment 64
innodb_autoinc_lock_mode    1
innodb_buffer_pool_chunk_size   134217728
innodb_buffer_pool_dump_at_shutdown ON
innodb_buffer_pool_dump_now OFF
innodb_buffer_pool_dump_pct 25
innodb_buffer_pool_filename ib_buffer_pool
innodb_buffer_pool_instances    1
innodb_buffer_pool_load_abort   OFF
innodb_buffer_pool_load_at_startup  ON
innodb_buffer_pool_load_now OFF
innodb_buffer_pool_size 12884901888
innodb_change_buffer_max_size   25
innodb_change_buffering all
innodb_checksum_algorithm   crc32
innodb_checksums    ON
innodb_cmp_per_index_enabled    OFF
innodb_commit_concurrency   0
innodb_compression_failure_threshold_pct    5
innodb_compression_level    6
innodb_compression_pad_pct_max  50
innodb_concurrency_tickets  5000
innodb_data_file_path   ibdata1:12M:autoextend
innodb_data_home_dir     
innodb_deadlock_detect  ON
innodb_default_row_format   dynamic
innodb_disable_sort_file_cache  OFF
innodb_doublewrite  ON
innodb_fast_shutdown    1
innodb_file_format  Barracuda
innodb_file_format_check    ON
innodb_file_format_max  Barracuda
innodb_file_per_table   ON
innodb_fill_factor  100
innodb_flush_log_at_timeout 1
innodb_flush_log_at_trx_commit  2
innodb_flush_method O_DIRECT
innodb_flush_neighbors  1
innodb_flush_sync   ON
innodb_flushing_avg_loops   30
innodb_force_load_corrupted OFF
innodb_force_recovery   0
innodb_ft_aux_table  
innodb_ft_cache_size    8000000
innodb_ft_enable_diag_print OFF
innodb_ft_enable_stopword   ON
innodb_ft_max_token_size    84
innodb_ft_min_token_size    3
innodb_ft_num_word_optimize 2000
innodb_ft_result_cache_limit    2000000000
innodb_ft_server_stopword_table  
innodb_ft_sort_pll_degree   2
innodb_ft_total_cache_size  640000000
innodb_ft_user_stopword_table    
innodb_io_capacity  200
innodb_io_capacity_max  2000
innodb_large_prefix ON
innodb_lock_wait_timeout    120
innodb_locks_unsafe_for_binlog  OFF
innodb_log_buffer_size  41943040
innodb_log_checksums    ON
innodb_log_compressed_pages ON
innodb_log_file_size    1048576000
innodb_log_files_in_group   2
innodb_log_group_home_dir   ./
innodb_log_write_ahead_size 8192
innodb_lru_scan_depth   1024
innodb_max_dirty_pages_pct  75.000000
innodb_max_dirty_pages_pct_lwm  0.000000
innodb_max_purge_lag    0
innodb_max_purge_lag_delay  0
innodb_max_undo_log_size    1073741824
innodb_monitor_disable   
innodb_monitor_enable    
innodb_monitor_reset     
innodb_monitor_reset_all     
innodb_old_blocks_pct   37
innodb_old_blocks_time  1000
innodb_online_alter_log_max_size    134217728
innodb_open_files   1520
innodb_optimize_fulltext_only   OFF
innodb_page_cleaners    1
innodb_page_size    16384
innodb_print_all_deadlocks  OFF
innodb_purge_batch_size 300
innodb_purge_rseg_truncate_frequency    128
innodb_purge_threads    4
innodb_random_read_ahead    OFF
innodb_read_ahead_threshold 56
innodb_read_io_threads  4
innodb_read_only    OFF
innodb_replication_delay    0
innodb_rollback_on_timeout  OFF
innodb_rollback_segments    128
innodb_sort_buffer_size 1048576
innodb_spin_wait_delay  6
innodb_stats_auto_recalc    ON
innodb_stats_method nulls_equal
innodb_stats_on_metadata    OFF
innodb_stats_persistent ON
innodb_stats_persistent_sample_pages    20
innodb_stats_sample_pages   8
innodb_stats_transient_sample_pages 8
innodb_status_output    OFF
innodb_status_output_locks  OFF
innodb_strict_mode  ON
innodb_support_xa   ON
innodb_sync_array_size  1
innodb_sync_spin_loops  30
innodb_table_locks  ON
innodb_temp_data_file_path  ibtmp1:12M:autoextend
innodb_thread_concurrency   0
innodb_thread_sleep_delay   10000
innodb_tmpdir    
innodb_undo_directory   ./
innodb_undo_log_truncate    OFF
innodb_undo_logs    128
innodb_undo_tablespaces 0
innodb_use_native_aio   ON
innodb_version  5.7.16
innodb_write_io_threads 4
insert_id   0
interactive_timeout 43200
internal_tmp_disk_storage_engine    InnoDB
join_buffer_size    262144
keep_files_on_create    OFF
key_buffer_size 8388608
key_cache_age_threshold 300
key_cache_block_size    1024
key_cache_division_limit    100
large_files_support ON
large_page_size 0
large_pages OFF
last_insert_id  0
lc_messages en_US
lc_messages_dir /usr/share/mysql/
lc_time_names   en_US
license GPL
local_infile    ON
lock_wait_timeout   31536000
locked_in_memory    OFF
log_bin ON
log_bin_basename    /mnt/data/mysql/mysql-bin
log_bin_index   /mnt/data/mysql/mysql-bin.index
log_bin_trust_function_creators ON
log_bin_use_v1_row_events   OFF
log_builtin_as_identified_by_password   OFF
log_error   /var/log/mysqld.log
log_error_verbosity 3
log_output  FILE
log_queries_not_using_indexes   ON
log_slave_updates   OFF
log_slow_admin_statements   OFF
log_slow_slave_statements   OFF
log_statements_unsafe_for_binlog    ON
log_syslog  OFF
log_syslog_facility daemon
log_syslog_include_pid  ON
log_syslog_tag   
log_throttle_queries_not_using_indexes  0
log_timestamps  UTC
log_warnings    2
long_query_time 1.000000
low_priority_updates    OFF
lower_case_file_system  OFF
lower_case_table_names  1
master_info_repository  FILE
master_verify_checksum  OFF
max_allowed_packet  1073741824
max_binlog_cache_size   18446744073709547520
max_binlog_size 1073741824
max_binlog_stmt_cache_size  18446744073709547520
max_connect_errors  100
max_connections 4000
max_delayed_threads 20
max_digest_length   1024
max_error_count 64
max_execution_time  0
max_heap_table_size 1073741824
max_insert_delayed_threads  20
max_join_size   18446744073709551615
max_length_for_sort_data    1024
max_points_in_geometry  65536
max_prepared_stmt_count 16382
max_relay_log_size  0
max_seeks_for_key   18446744073709551615
max_sort_length 1024
max_sp_recursion_depth  0
max_tmp_tables  32
max_user_connections    0
max_write_lock_count    18446744073709551615
metadata_locks_cache_size   1024
metadata_locks_hash_instances   8
min_examined_row_limit  0
multi_range_count   256
myisam_data_pointer_size    6
myisam_max_sort_file_size   9223372036853727232
myisam_mmap_size    18446744073709551615
myisam_recover_options  OFF
myisam_repair_threads   1
myisam_sort_buffer_size 8388608
myisam_stats_method nulls_unequal
myisam_use_mmap OFF
mysql_native_password_proxy_users   OFF
net_buffer_length   16384
net_read_timeout    30
net_retry_count 10
net_write_timeout   60
new OFF
ngram_token_size    2
offline_mode    OFF
old OFF
old_alter_table OFF
old_passwords   0
open_files_limit    40000
optimizer_prune_level   1
optimizer_search_depth  62
optimizer_switch    index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,engine_condition_pushdown=on,index_condition_pushdown=on,mrr=on,mrr_cost_based=on,block_nested_loop=on,batched_key_access=off,materialization=on,semijoin=on,loosescan=on,firstmatch=on,duplicateweedout=on,subquery_materialization_cost_based=on,use_index_extensions=on,condition_fanout_filter=on,derived_merge=on
optimizer_trace enabled=off,one_line=off
optimizer_trace_features    greedy_search=on,range_optimizer=on,dynamic_range=on,repeated_subselect=on
optimizer_trace_limit   1
optimizer_trace_max_mem_size    16384
optimizer_trace_offset  -1
parser_max_mem_size 18446744073709551615
performance_schema  ON
performance_schema_accounts_size    -1
performance_schema_digests_size 10000
performance_schema_events_stages_history_long_size  10000
performance_schema_events_stages_history_size   10
performance_schema_events_statements_history_long_size  10000
performance_schema_events_statements_history_size   10
performance_schema_events_transactions_history_long_size    10000
performance_schema_events_transactions_history_size 10
performance_schema_events_waits_history_long_size   10000
performance_schema_events_waits_history_size    10
performance_schema_hosts_size   -1
performance_schema_max_cond_classes 80
performance_schema_max_cond_instances   -1
performance_schema_max_digest_length    1024
performance_schema_max_file_classes 80
performance_schema_max_file_handles 32768
performance_schema_max_file_instances   -1
performance_schema_max_index_stat   -1
performance_schema_max_memory_classes   320
performance_schema_max_metadata_locks   -1
performance_schema_max_mutex_classes    200
performance_schema_max_mutex_instances  -1
performance_schema_max_prepared_statements_instances    -1
performance_schema_max_program_instances    -1
performance_schema_max_rwlock_classes   40
performance_schema_max_rwlock_instances -1
performance_schema_max_socket_classes   10
performance_schema_max_socket_instances -1
performance_schema_max_sql_text_length  1024
performance_schema_max_stage_classes    150
performance_schema_max_statement_classes    193
performance_schema_max_statement_stack  10
performance_schema_max_table_handles    -1
performance_schema_max_table_instances  -1
performance_schema_max_table_lock_stat  -1
performance_schema_max_thread_classes   50
performance_schema_max_thread_instances -1
performance_schema_session_connect_attrs_size   512
performance_schema_setup_actors_size    -1
performance_schema_setup_objects_size   -1
performance_schema_users_size   -1
pid_file    /var/run/mysqld/mysqld.pid
plugin_dir  /usr/lib64/mysql/plugin/
port    3306
preload_buffer_size 32768
profiling   OFF
profiling_history_size  15
protocol_version    10
proxy_user   
pseudo_slave_mode   OFF
pseudo_thread_id    21979
query_alloc_block_size  8192
query_cache_limit   0
query_cache_min_res_unit    4096
query_cache_size    0
query_cache_type    OFF
query_cache_wlock_invalidate    OFF
query_prealloc_size 8192
rand_seed1  0
rand_seed2  0
range_alloc_block_size  4096
range_optimizer_max_mem_size    8388608
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relay_log   /mnt/data/mysql/mysqld-relay-bin
relay_log_basename  /mnt/data/mysql/mysqld-relay-bin
relay_log_index /mnt/data/mysql/mysqld-relay-bin.index
relay_log_info_file relay-log.info
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session_track_gtids OFF
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session_track_transaction_info  OFF
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skip_external_locking   ON
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skip_networking OFF
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time_format %H:%i:%s
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timestamp   1482351343.091002
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version_comment MySQL Community Server (GPL)
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0

2 Answers 2

3
  • max_connections=8000 -- Unreasonably high. If you really do get anywhere near 8000 connections, look into throttling it before it gets to MySQL
  • tmp_table_size = 1G and max_heap_table_size = 1G -- Since tmp tables are potentially allocated for each SELECT (and each subquery), threatens to need more than 8TB. I recommend no more than 1% of RAM (for each) until you find a specific need for more.
  • innodb_buffer_pool_size=9G -- Reasonable for 15GB of RAM; is that how much you have? This is the first thing to decrease if you are in a hurry to recover from repeated crashes.
  • group_concat_max_len = 1M -- Recommend setting this only for connections that will be doing fat GROUP_CONCATs.

  • swap is not enabled -- Swapping is bad for performance, but being killed is worse. Suggest enabling swap and setting swappiness = 1 in the OS.

For more critique, provide SHOW VARIABLES; and SHOW GLOBAL STATUS;.

1
  • Comments are not for extended discussion; this conversation has been moved to chat.
    – Paul White
    Dec 21, 2016 at 1:44
2

Community Wiki answer generated from comments by the question author

The issue was with innodb_buffer_pool_instances which is default 8 on MySQL 5.7 and 1 on MySQL 5.5, after I changed it back to 1, problem solved.

Anyway, I think max connections is too high, so I going to reduce it to 4000 at the beginning and decrease little bit the innodb buffer pool size, or maybe take a machine with more memory.

I know 4000 is high, but I don't want to make a huge change on production so I changed it from 8000 to 4000, later on I can reduce it more. Max_used_connections shows 391, we configured Hibernate config connection pool size to 800.

I changed separately and waited two days and the DB was not crashed, but anyway like I said before, I used http://www.mysqlcalculator.com and adjusted the configurations in my.cnf to the memory that I actually have on the server. Reducing max_connections from 8000 to 4000 saved me a lot of memory, I saw that on zabbix.

I took m4.2xlarge with 32 GB memory, and changed innodb_buffer_pool_size=15, max_connections=4000.

mysqlcalculator showed with the old configuration that I didn't have enough memory for MySQL to run properly, so I think always need to check configuration with MySQL calc in order to understand the memory usage on the server.

Just to clarify: The tuning settings that I wrote above were the solution to the crashes issue, but the aborted connections might come from the application side, I still see these note messages in the log, but for now it seems that everything works properly.

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