Very slow unbuffered logging

We were using buffered loggin, but I think that it's not secure because that doesn't assure that the commited transactions are saved in case of energy supply, etc. So we changed to unbuffered logging and the performance of the machine as a whole came down. Using tbstat -u we saw users waiting for logical buffers. The logical log buffer is configured for 16 pages. We have Informix 5.10 UC1. When we changed to buffered logging everything got ok again. Is this the expected result? Does unbuffered logging make the machine very slow? Is buffered logging the best choice? Another thing, I thought of lowering the logical log buffer to 1 page, but the database says the minimun value is 16 pages. Thanks in advance, -- Ricardo Palmeira Tribunal de Contas do Estado de Pernambuco mailto:palmeira@tce.pe.gov.br