DB Error: Table './ojs/sessions' is marked as crashed and should be repaired

Stack Trace:

File: /var/www/html/ojs/lib/pkp/classes/session/SessionDAO.inc.php line 38
Function: DAO->retrieve("SELECT * FROM sessions WHERE session_id = ?", Array(1))

File: /var/www/html/ojs/lib/pkp/classes/session/SessionManager.inc.php line 168
Function: SessionDAO->getSession("1b4q7p0cndc7jp2n06k5kacs00")

File: (unknown) line (unknown)
Function: SessionManager->read("1b4q7p0cndc7jp2n06k5kacs00")

File: /var/www/html/ojs/lib/pkp/classes/session/SessionManager.inc.php line 58
Function: session_start()

File: /var/www/html/ojs/lib/pkp/classes/session/SessionManager.inc.php line 129
Function: SessionManager->__construct(Object(SessionDAO), Object(Request))

File: /var/www/html/ojs/lib/pkp/classes/security/Validation.inc.php line 366
Function: SessionManager::getManager()

File: /var/www/html/ojs/lib/pkp/classes/core/PKPPageRouter.inc.php line 67
Function: Validation::isLoggedIn()

File: /var/www/html/ojs/lib/pkp/classes/core/Dispatcher.inc.php line 117
Function: PKPPageRouter->isCacheable(Object(Request))

File: /var/www/html/ojs/lib/pkp/classes/core/PKPApplication.inc.php line 247
Function: Dispatcher->dispatch(Object(Request))

File: /var/www/html/ojs/index.php line 68
Function: PKPApplication->execute()