Consider the default input settings given by the tool. Only change is to make all resource utilizations to 100 %.

a. What units cost the most in this system?

b. What can be done to make the system cost same for both 80GB and 40GB disks? Can it be done?

1) We have assumed the resource utilizations to be 100% in the above cases. Is it the same in practice? Give reasons for your answer.

1) Give the key function for a transaction processing system and batch processing system.

Transaction Processing:

Batch Processing

Tool to Evaluate I/O Cost & Performance Input Values: CPU MIPS = 2500 MIPS CPU Cost = 20000 S Width of interleaved memory = 16 ns bytes Memory cycle time = 10 MB/sec Maximum number of SCSI buses and controllers = 20 I/O Bus bandwidth = 1000 SCSI Bus transfer rate = 160 MB/sec Maximum number of disks per SCSI string = 15 500 SCSI Controller overhead = 0.3 ms Cost of each SCSI controller = Number of CPU instructions for an I/O operation = 50000 Average I/O size = 32 KB Input Disk specifications: Disk size = small disk 40 GB large disk 80 GB Cost of Disk per GB = small disk 10 $ large disk 10 $ Maximum number of disks per package = small disk 12 large disk 8 Disk Rotation speed = small disk 15000 RPM large disk 15000 RPM Average seek time = small disk 5 ms large disk 5 ms Disk Transfer rate = small disk 40 MB/sec large disk 40 MB/sec Desired total disk capacity = 1920 GB Cost of enclosure = 1500 S Constraints on Resource Utilization: Limit on disk time utilization = 80 % Limit on utilization of SCSI buses = 40 % Limit on utilization of I/O bus = 75 % Reset Values Specs. of Organization Maximum IOPS Cost of Organization Resource Utilization Help Quit Tool to Evaluate I/O Cost & Performance Input Values: CPU MIPS = 2500 MIPS CPU Cost = 20000 S Width of interleaved memory = 16 ns bytes Memory cycle time = 10 MB/sec Maximum number of SCSI buses and controllers = 20 I/O Bus bandwidth = 1000 SCSI Bus transfer rate = 160 MB/sec Maximum number of disks per SCSI string = 15 500 SCSI Controller overhead = 0.3 ms Cost of each SCSI controller = Number of CPU instructions for an I/O operation = 50000 Average I/O size = 32 KB Input Disk specifications: Disk size = small disk 40 GB large disk 80 GB Cost of Disk per GB = small disk 10 $ large disk 10 $ Maximum number of disks per package = small disk 12 large disk 8 Disk Rotation speed = small disk 15000 RPM large disk 15000 RPM Average seek time = small disk 5 ms large disk 5 ms Disk Transfer rate = small disk 40 MB/sec large disk 40 MB/sec Desired total disk capacity = 1920 GB Cost of enclosure = 1500 S Constraints on Resource Utilization: Limit on disk time utilization = 80 % Limit on utilization of SCSI buses = 40 % Limit on utilization of I/O bus = 75 % Reset Values Specs. of Organization Maximum IOPS Cost of Organization Resource Utilization Help Quit