Here is a fix: https://github.com/glpi-project/glpi/pull/4531 .
Regards
]]>Maybe there is a bug.
I change to 2 month and run the task. The log http://yourip/front/event.php was cleaned but i had history logs from year 2016 in my computer history. I changed to delete all and the history logs go away...
Check Setup > General menu, log purge tab to set it up
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