Db.c disk i/o error, dropped calls

Every few hours, I get the following in the asterisk log.

[2018-09-16 23:47:36] WARNING[2576] db.c: Error executing SQL (COMMIT): disk I/O error
[2018-09-16 23:47:36] WARNING[2576] db.c: Error executing SQL (ROLLBACK): cannot rollback - no transaction is active

Then the call drops. It doesn’t happen every time, probably 2 times a day.

I tried running mysqlcheck --all-databases --extended, no errors detected.

I tried running xfs_check on the drive, no errors detected.

I even tried building a new VM and restoring the application backup. The error continues to appear even on the new machine.

It is hosted on ESXI 6.5 on a high performance machine, disk is RAID-5, memory is 10 gigs. (It’s only using 1.5 gigs).

I checked the messages log at that time, and also the mariadb.log. There were no log entries written at that time.

Asterisk 15.5.0
MariaDB 5.5.56
Platform is Sangoma Linux release 7.5.1805 (Core)