You are working on an online transaction processing (OLTP) database that runs on a machine having multiple CPUs. The database uses normal file system storage. Examine the following initialization parameters and their respective values for the instance:
NAME TYPE VALUE
———————————— ———- ———————-
dbwr_io_slaves integer 0
db_writer_processes integer 1
filesystemio_options string NONE
disk_asynch_io boolean TRUE
The applications perform small, random I/Os in which each foreground process reads a data block into the buffer cache for updates and the changed blocks are written in batches by the DBWR process. You noticed free buffer waits events for your database. To solve the problem, you increased the size of the buffer cache. But after some time, you notice the same event again.
Which three possible actions would you recommend? (Choose three.)
A.
configuring multiple DBWR processes
B.
decreasing the size of the buffer cache
C.
configuring I/O slaves for the DBWR process
D.
configuring instances to make asynchronous I/O available to DBWR
E.
spread data files over multiple disks, controllers, and I/O buses to ensure that there are no hotspots in the I/O subsystem