Edit: Just tested 10.11.2 - happens there as well

When parallel importing large amounts of datasets into the same table the imports suddenly hang at certain times. This sometimes happens after a few seconds, sometimes after a few minutes... at that point there have sometimes been 50MB of data imported, sometimes 1-2GB...

in the processlist it looks like this - the time continues to go up, but nothing happens anymore, even after 50+ hours.

I also can't kill the queries. If I stop the original process that imported them - nothing happens. If I kill the query on the console the status switches from Update to "killed" - but that's it. I have to kill -9 the whole database.

This does not happen with 10.6.11
It happens on different servers with different amounts of CPU / memory / harddrive combinations on debian11 and debian10 with the versions from the mariadb apt repository

Attached is an output of show global variables.

To have a testcase outside of our application, I created the following table in an empty database:

CREATE TABLE `testtable` (

  `test01` decimal(24,6) DEFAULT NULL,

  `test02` bigint(20) DEFAULT NULL,

  `test03` varchar(255) DEFAULT NULL,

  `test04` varchar(255) DEFAULT NULL,

  `test05` varchar(100) DEFAULT NULL,

  `test06` varchar(255) DEFAULT NULL,

  `test07` varchar(255) DEFAULT NULL,

  `test08` varchar(255) DEFAULT NULL,

  `test09` varchar(255) DEFAULT NULL,

  `test10` varchar(255) DEFAULT NULL,

  `test11` varchar(255) DEFAULT NULL,

  `test12` varchar(255) DEFAULT NULL,

  `test13` varchar(255) DEFAULT NULL,

  `test14` varchar(8) DEFAULT NULL,

  `test15` varchar(255) DEFAULT NULL,

  `test16` varchar(255) DEFAULT NULL,

  `test17` varchar(255) DEFAULT NULL,

  `test18` varchar(255) DEFAULT NULL,

  `test19` varchar(255) DEFAULT NULL,

  `test20` varchar(255) DEFAULT NULL,

  `test21` varchar(50) DEFAULT NULL,

  `test22` varchar(255) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci

Then I generated four SQL files with random test data using https://filldb.info/dummy

and ran a bash script like this

#!/bin/bash

# Drop and recreate table, disable keys, lock table

mysql emptytest < testtable1.sql

sleep 2

# parallel import data

mysql emptytest < testtable2.sql &

mysql emptytest < testtable3.sql &

mysql emptytest < testtable4.sql &

mysql emptytest < testtable5.sql &

wait $(jobs -p)

sleep 2

#reenable keys, unlock table

mysql emptytest < testtable6.sql

I then loop over this

while true; do; ./import.sh ; done

And wait... it happens usually after a few minutes with 10.6.12.

Not sure if (and if so how / where) I should upload the complete testdata set, it's multiple gb big and basically just useless data - so please let me know how I can help