MySQL my.cnf performance tuning recommendations
Your innodb_buffer_pool_size is almost absurdly small for a server of that size.
innodb_flush_log_at_trx_commit=2  is dangerous.
innodb_file_per_table=1 you definitely don't want commended out. Rebuild any tables that aren't in separate tablespaces.
query_cache_limit=1G makes no sense with query cache disabled.
Various buffer sizes other than innodb_buffer_pool_size - you should probably leave them at default settings. Comment them out. Especially join_buffer_size and sort_buffer_size.
Do you use MyISAM? If not, reduce key_buffer_size down to something tiny (enough to cover the size of all .MYI files in your database.