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DISKS
Disk Hardware
1. Magnetic disk
• Cylindes, tracks
• IDE (Integrated Drive Electronics)
• Overlapped seek
• Logical block addressing
Physical geometry vs possible virtual geometry
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2. RAID
Redundant Array of Inexpensive Disks
3. CD-ROMS
Struktur penyimpanan dari CD atau CD-RO
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Logical data layout pada CD-ROM
Format Disk
Suatu sektor pada disk
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Interleaving
• No interleaving
• Single interleaving
• Double interleaving
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Disk Arm Scheduling Algorithms (1)
• Tiga faktor yang menentukan waktu baca atau tulis
pada disk block :
• Seek time
• Rotational delay
• Actual transfer time
• Seek time yang paling dominan
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Algoritma Penjadwalan Lengan Disk
1. First Come First Serve (FCFS)
2. Shortest Seek First (SSF)
3. Elevator