If you are in Oracle Server - Enterprise Edition - Version: 10.2.0.1 and operating system HP-UX PA-RISC (64-bit) and have set:
disk_asynch_io = TRUE and sga_target > 4G
then the instance fails to startup with error:
ORA-27061: waiting for async I/Os failed
By setting disk_asynch_io = FALSE you can bypass the problem, but you cannot work efficient.
:It is better to set sga_target = 3728MB to startup the instance
: There is a one-off patch (Patch 4709673) available for Oracle 10.2.0.1