Uncaught exception thrown in session handler.

PDOException: SQLSTATE[HY000]: General error: 1114 The table 'sessions' is full: INSERT INTO {sessions} (sid, ssid, uid, cache, hostname, session, timestamp) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6); Array ( [:db_insert_placeholder_0] => HUKmZBkhb4vfBQcyHzo1UtWs4D39RV1q-_oZ3mPAozg [:db_insert_placeholder_1] => [:db_insert_placeholder_2] => 0 [:db_insert_placeholder_3] => 0 [:db_insert_placeholder_4] => 18.97.14.91 [:db_insert_placeholder_5] => messages|a:1:{s:5:"error";a:2:{i:0;s:327:"<em class="placeholder">Notice</em>: file_put_contents(): write of 8192 bytes failed with errno=28 No space left on device in <em class="placeholder">boost_write_file()</em> (line <em class="placeholder">1363</em> of <em class="placeholder">/var/www/html/grumpyferret.com/public_html/sites/all/modules/boost/boost.module</em>).";i:1;s:327:"<em class="placeholder">Warning</em>: file_put_contents(): Only -1 of 10585 bytes written, possibly out of free disk space in <em class="placeholder">boost_write_file()</em> (line <em class="placeholder">1363</em> of <em class="placeholder">/var/www/html/grumpyferret.com/public_html/sites/all/modules/boost/boost.module</em>).";}} [:db_insert_placeholder_6] => 1733538276 ) in _drupal_session_write() (line 212 of /var/www/html/grumpyferret.com/public_html/includes/session.inc).