windows (server 2019) and linux ubuntu

How long after restarting the service until the problem presents itself again? At the moment it looks like your table_open_cache is insufficient. Can you include your configuration and SHOW GLOBAL STATUS at the time of contention.

The problem reoccurs sporadically, sometimes it takes days and sometimes twice a day.
The table_open_cache parameter is table_open_cache=16384 the database has 3000 tables and we have 200 concurrent sessions.

my,cnf:

[mysqld]

skip-networking=0

lower_case_table_names=1

innodb_file_per_table=1

query_cache_type=OFF

innodb_log_file_size=1024M

innodb_log_buffer_size=128M

innodb_flush_log_at_trx_commit=0

tmp_table_size=200M

max_heap_table_size=200M

performance_schema=1

key_buffer_size=1M

table_open_cache=16384

table_definition_cache=16384

thread_handling=pool-of-threads

net_write_timeout=3600

net_read_timeout=600

max_allowed_packet=268435456

connect_timeout=60

innodb_buffer_pool_size=512M

port=3306

socket=/usr/local/mysql/data/mysql.sock

log_error=/usr/local/mysql/data/log_error.log

max_connections=700

log_bin=/usr/local/mysql/binlog/mysql-bin.log

max_binlog_size=512M

server_id=1

expire_logs_days=1

binlog_format=mixed

open_files_limit=102400

log_bin_trust_function_creators=1

[client]

socket=/usr/local/mysql/data/mysql.sock

When it crashes again I will post the data of "SHOW GLOBAL STATUS".

Thanks e best regards !

Could this be swap related? innodb_buffer_pool_size looks rather small. How much memory do you have? tmp_table_size/max_heap_table_size is per connection so large in memory operations might end up running out of memory?

The server has only 8gb of memory, and no swap is detected. The crash seems to occur when very long reads are being performed (BI). The tmp_table_size is no longer used so I'm going to remove it, we used tables with ENGINE MEMORY.
So far, no crash has occurred, if it does I will post a "SHOW GLOBAL STATUS" and a "SHOW ENGINE INNODB STATUS".

ANDRE_DBA, there was a month with no feedback. I hope it means MariaDB didn't crash for you. I'll tentatively close this issue then, but whenever you want to add more info — just add a comment and I'll reopen it again. Thanks.