MariaDB Block Queries Indefinitely Under Non-Heavy Load

The database is working fine, then all of a sudden and update query hangs, and subsequent to that, another hang shows up in an unrelated table. After that, the table hangs until a restart of MariaDB. This hang leaves thousands of blocked transactions. The setup is read-uncommitted which has never been an issue. Below is a snippet from the SHOW PROCESSLIST ordered by TIME descending.

The table grid_blstat_service_domains has less than 20 rows. Why would it block like this? I've been reading that the setting:

innodb_snapshot_isolation=ON may have something to do with this. I have asked the user to disabled that setting in hopes that this is the issue. Also asked for a SHOW ENGINE INNODB STATUS\G if it happens again.

Id User Host db Command Time State Info Progress
20160194 cacti localhost cacti Query 27536 Updating UPDATE grid_blstat_service_domains SET present=0 WHERE lsid='1' 0
10 cacti localhost cacti Query 27535 Update REPLACE INTO settings SET name='lic_prev_start_server_1', value='1778774090' 0
20165783 cacti localhost cacti Execute 27535 Statistics SELECT value FROM settings WHERE name='lic_path_lm_output_1' 0
20165691 cacti localhost cacti Query 27534 Update INSERT INTO grid_jobs (job_start_logged,jobid,indexid,clusterid,user,stat,exitStatus,pendReasons,que 0
20164818 cacti localhost cacti Query 27533 Update INSERT INTO grid_reservations_jobs (clusterid, rsvId, jobid, indexid, status) VALUES ('2', 'dcs_desi 0
20165786 cacti localhost cacti Query 27532 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20164822 cacti localhost cacti Query 27531 Update INSERT INTO grid_job_groups (clusterid, groupName, numJobs, pendJobs, runJobs, suspJobs, finishJobs, 0
20163179 cacti localhost cacti Query 27530 Update INSERT INTO grid_jobs (job_start_logged,jobid,indexid,clusterid,user,stat,exitStatus,pendReasons,que 0
20164612 cacti localhost cacti Query 27528 Opening tables INSERT INTO grid_jobs_jobhosts (jobid,indexid,clusterid,exec_host,submit_time,processes) VALUES ('1 0
20165787 cacti localhost cacti Query 27525 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
18 cacti localhost cacti Query 27524 Opening tables REPLACE INTO settings SET name='grid_prev_minor_start_16', value='1778774100' 0
20165792 cacti localhost cacti Query 27524 Opening tables UPDATE grid_jobs SET job_end_logged=0 WHERE clusterid='16' AND stat NOT IN ('ZOMBI', 'DONE', 'EXIT', 0
20165793 cacti localhost cacti Query 27524 Opening tables UPDATE grid_jobs SET job_end_logged=0 WHERE clusterid='16' AND stat NOT IN ('ZOMBI', 'DONE', 'EXIT', 0
20165794 cacti localhost cacti Query 27524 Opening tables REPLACE INTO settings (name,value) VALUES ('grid_arrays_start_time_16',UNIX_TIMESTAMP()) 0
20165800 cacti localhost cacti Query 27523 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165803 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165804 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165805 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165806 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165807 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165808 cacti localhost cacti Query 27508 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165708 cacti localhost cacti Query 27507 Opening tables UPDATE grid_arrays SET stat='1' WHERE (clusterid='15') AND (stat='0') AND ((numExit + numDone = nu 0
20165817 cacti localhost cacti Query 27472 Sending data SELECT name, value FROM settings WHERE name IN ('auth_method', 'auth_cache_enabled', 'path_cactilog' 0
20165819 cacti localhost cacti Query 27465 Opening tables SELECT value FROM settings WHERE name = 'path_cactilog' 0