DB Error: MySQL server has gone away

Stack Trace:

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/scheduledTask/ScheduledTaskDAO.inc.php line 41
Function: DAO->retrieve("SELECT last_run FROM scheduled_tasks WHERE class_name = ?", Array(1))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/scheduledTask/ScheduledTaskHelper.inc.php line 85
Function: ScheduledTaskDAO->getLastRunTime("plugins.generic.usageStats.UsageStatsLoader")

File: /home/storage/c/19/95/icesp1/public_html/revistas/plugins/generic/acron/AcronPlugin.inc.php line 355
Function: ScheduledTaskHelper->checkFrequency("plugins.generic.usageStats.UsageStatsLoader", Object(XMLNode))

File: /home/storage/c/19/95/icesp1/public_html/revistas/plugins/generic/acron/AcronPlugin.inc.php line 140
Function: AcronPlugin->_getTasksToRun()

File: (unknown) line (unknown)
Function: AcronPlugin->callbackLoadHandler("LoadHandler", Array(3))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/plugins/HookRegistry.inc.php line 89
Function: call_user_func(Array(2), "LoadHandler", Array(3))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/core/PKPPageRouter.inc.php line 178
Function: HookRegistry->call("LoadHandler", Array(3))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/core/Dispatcher.inc.php line 134
Function: PKPPageRouter->route(Object(Request))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/core/PKPApplication.inc.php line 178
Function: Dispatcher->dispatch(Object(Request))

File: /home/storage/c/19/95/icesp1/public_html/revistas/index.php line 64
Function: PKPApplication->execute()

DB Error: MySQL server has gone away

Stack Trace:

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/session/SessionDAO.inc.php line 119
Function: DAO->update("UPDATE sessions SET user_id = ?, ip_address = ?, ...", Array(9))

File: /home/storage/c/19/95/icesp1/public_html/revistas/lib/pkp/classes/session/SessionManager.inc.php line 186
Function: SessionDAO->updateObject(Object(Session))

File: (unknown) line (unknown)
Function: SessionManager->write("568e37ffc1c08b95fb1e3b9f50673340", "")

File: (unknown) line (unknown)
Function: session_write_close()