Latihan Soal Penyimpanan Sekunder

Soal!

Diketahui :

• Seek time (s) = 10 ms
• Kecepatan putar harddsik = 3000 rpm
• Transfer rate (t) = 1024 byte/s
• Ukuran blok (B) = 2048 byte
• Ukuran record (R) = 128 byte
• Ukuran gap (G) = 64 byte
• Ukuran pointer (P) = 10

Cari r, Bfr, T_R, Btt, W dan t'! (Menggunakan metode fixed blocking, spanned blocking dan unspanned blocking!)

Jawaban :

1. r = ¹/₂ * (^{(60 * 1000)}/_RPM)
   r = ¹/₂ * (^{(60 * 1000)}/₃₀₀₀)
   r = 10 s

2. Bfr

§  Fixed Blocking

Bfr = ^B/_R
Bfr = ²⁰⁴⁸/128
Bfr = 16

§  Spanned Blocking

Bfr = (B - P) / (R + P)
Bfr = (2048 - 10) / (128 + 10)
Bfr = 14,76

§  Unspanned Blocking

Bfr = (B - ¹ / ₂R)/(R + P)
Bfr = (2048 - ¹ / ₂128)/(128 + 10)
Bfr = 14,37

3. T_R = ^R/_t
   T_R = ¹²⁸/₁₀₂₄
   T_R = 0,125

4. Btt = ^B/_t
   Btt = ²⁰⁴⁸/₁₀₂₄
   Btt = 2
   
   
5. W

§  Fixed Blocking

W_G = ^G / _Bfr
W_G = ⁶⁴ / ₁₆
W_G = 4

W_R = ^B / _Bfr
W_R = ²⁰⁴⁸ / ₁₆
W_R = 128

W = W_G + W_R
W = 4 + 128
W = 132

§  Spanned Blocking

W = P + (P + G) / Bfr
W = 10 + (10 + 64) / 14,76
W = 15,01

§  Unspanned Blocking

W = P + (¹/₂R + G) / Bfr
W = 10 + (¹/₂128 + 64) / 14,37
W = 18,9

6. t'

§  Fixed Blocking

t' = (^t/₂) * {R / (R + W)}
t' = (¹⁰²⁴/₂) * {128 / (128 + 132)}
t' = 250,88

§  Spanned Blocking

t' = (^t/₂) * {R / (R + W)}
t' = (¹⁰²⁴/₂) * {128 / (128 + 15,01)}
t' = 455,68

§  Unspanned Blocking

t' = (^t/₂) * {R / (R + W)}
t' = (¹⁰²⁴/₂) * {128 / (128 + 18,9)}
t' = 445,44