Xenforo Constantly getting MySQL error while running defer

I getting MySQL error everytime XF try to perform the defer task. Do you guys have any ideal on this.

Code:

Are you sure you want to upgrade? [y/n] y
Rebuilding / importing data...
Rebuilding... Templates  .
An exception occurred: mysqli_stmt::close(): Couldn't fetch mysqli_stmt in Zend/Db/Statement/Mysqli.php on line 105
#0 [internal function]: XenForo_Application::handlePhpError(2, 'mysqli_stmt::cl...', '/home/nginx/dom...', 105, Array)
#1 Zend/Db/Statement/Mysqli.php(105): mysqli_stmt->close()
#2 Zend/Db/Adapter/Mysqli.php(374): Zend_Db_Statement_Mysqli->close()
#3 Zend/Db/Adapter/Abstract.php(478): Zend_Db_Adapter_Mysqli->prepare('\r\n\t\t\t\tINSERT IN...')
#4 XenForo/Model/Deferred.php(116): Zend_Db_Adapter_Abstract->query('\r\n\t\t\t\tINSERT IN...', Array)
#5 XenForo/Application.php(1458): XenForo_Model_Deferred->defer('Atomic', Array, 'installUpgradeR...', 1, 1442941801)
#6 XenForo/Model/Deferred.php(311): XenForo_Application::defer('Atomic', Array, 'installUpgradeR...', 1, 1442941801, true)
#7 XenForo/Model/Deferred.php(429): XenForo_Model_Deferred->runDeferred(Array, 7.9999949932098, 'Rebuilding... T...', false)
#8 XenForo/Model/Deferred.php(355): XenForo_Model_Deferred->_runInternal(Array, NULL, 'Rebuilding... T...', false)
#9 XenForo/Install/run-upgrade.php(170): XenForo_Model_Deferred->runByUniqueKey('installUpgradeR...', NULL, 'Rebuilding... T...')
#10 {main}

Are you sure you want to upgrade? [y/n] y
Rebuilding / importing data...
Importing... Phrases  .
An exception occurred: Mysqli prepare error: MySQL server has gone away in Zend/Db/Statement/Mysqli.php on line 77
#0 Zend/Db/Statement.php(115): Zend_Db_Statement_Mysqli->_prepare('\r\n\t\t\t\tINSERT IN...')
#1 Zend/Db/Adapter/Mysqli.php(381): Zend_Db_Statement->__construct(Object(Zend_Db_Adapter_Mysqli), '\r\n\t\t\t\tINSERT IN...')
#2 Zend/Db/Adapter/Abstract.php(478): Zend_Db_Adapter_Mysqli->prepare('\r\n\t\t\t\tINSERT IN...')
#3 XenForo/Model/Deferred.php(139): Zend_Db_Adapter_Abstract->query('\r\n\t\t\t\tINSERT IN...', Array)
#4 XenForo/Application.php(1458): XenForo_Model_Deferred->defer('Atomic', Array, 'installUpgradeR...', 1, 1442941910)
#5 XenForo/Model/Deferred.php(311): XenForo_Application::defer('Atomic', Array, 'installUpgradeR...', 1, 1442941910, true)
#6 XenForo/Model/Deferred.php(429): XenForo_Model_Deferred->runDeferred(Array, 7.9999349117279, 'Importing... Ph...', false)
#7 XenForo/Model/Deferred.php(355): XenForo_Model_Deferred->_runInternal(Array, NULL, 'Importing... Ph...', false)
#8 XenForo/Install/run-upgrade.php(170): XenForo_Model_Deferred->runByUniqueKey('installUpgradeR...', NULL, 'Importing... Ph...')
#9 {main}

This is the error log from XF upgrade via CLI, same for install/upgrade add-ons

Current system:
Digital Ocean 512MB droplet.
CentOS 6.5
PHP 5.6.12
nginx 1.9.4
MariaDB 10.0.21

---

 

Code:

#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d

[mysqld]
character-set-server=utf8

[mariadb-10.0]
# 2 variables needed to switch from XtraDB to InnoDB plugins
#plugin-load=ha_innodb
#ignore_builtin_innodb

## MariaDB 10 InnoDB plugin only
#innodb_buffer_pool_load_now=1
#innodb_buffer_pool_dump_now=1
## Disabled settings
performance_schema=OFF
innodb_stats_on_metadata=OFF
innodb_sort_buffer_size=2M
innodb_online_alter_log_max_size=128M
query_cache_strip_comments=0
log_slow_filter =admin,filesort,filesort_on_disk,full_join,full_scan,query_cache,query_cache_miss,tmp_table,tmp_table_on_disk

my.cnf

The DB size is 97.8MB with ~ 132k total records.
My XF forum has 9 add-ons and 1 style

 

Yes, I did.

 

K, is this good for 512MB droplet?

 

Done. I'll try to ugrade XF to 1.5.2 now.

 

Successfully upgrade to 1.5.2 without error. Thanks