Issue Mariadb stop responding

[OlivierV]

Hello,
We use Plesk 12.5.30 on Centos 7 with an application with lot's of user connected on.
Sometimes Mariadb is not responding and I have in Php log : The server "MySQL server has gone away" on a simple request in a little table.
We must restart mariadb service, but all session are broken.
We have nothing in the mariadb log file...

The main database used for this application is 873.3 Mio large using MyIsam

Can someone help us to know where is the problem ?

Thank you for your help.

 

[IgorG]

To fix, check that “wait_timeout” mysql variable in your my.cnf configuration file is large enough. Also you can increase the maximal packet size limit “max_allowed_packet” in my.cnf file, eg. set max_allowed_packet = 128M, then restart mariadb service.

 

[OlivierV]

Hello,

Thank you for this help I will modify the cnf file and wait if the problem disappeared. The old value was 16M.
My server have 64Go of RAM.
Here is my configuration file :

[mysqld]
local-infile=0
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
#max_connections=300

####OPTIMISATION TEST#####

max_connections=448
max_user_connections=30
key_buffer=4096M
myisam_sort_buffer_size=64M
join_buffer_size=1M
read_buffer_size=32M
sort_buffer_size=32M
table_open_cache=1500
thread_concurrency=10
thread_cache_size=128M
max_allowed_packet=128M
query_cache_limit=1M
query_cache_size=1024M
query_cache_type=1
table_definition_cache=1150
slow_query_log=1
#####END TEST######

### Test ###
low_priority_updates=1
concurrent_insert=ALWAYS

[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid
#
# include all files from the config directory
#
!includedir /etc/my.cnf.d